PD-1 antibodies

ABSTRACT

A humanised agonistic antibody which binds human PD-1 comprising a heavy chain and a light chain wherein the variable domain of the heavy chain comprises the sequence given in SEQ ID NO:1 for CDR-H1, the sequence given in SEQ ID NO:2 for CDR-H2 and the sequence given in SEQ ID NO:3 for CDR-H3 and the variable domain of the light chain comprises the sequence given in SEQ ID NO:4 for CDR-L1, the sequence given in SEQ ID NO:5 for CDR-L2 and the sequence given in SEQ ID NO:7 for CDR-L3. The invention also extends to therapeutic uses of the antibody molecules, compositions and methods for producing said antibody molecules.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to U.S. Application Ser. No.61/312,702, filed on Mar. 11, 2010, under 35 U.S.C. §119(e), which isincorporated by reference in its entirety.

FIELD OF THE INVENTION

The present invention relates to antibody molecules having specificityfor antigenic determinants of human PD-1 and compositions comprising thesame. The present invention also relates to the therapeutic uses of theantibody molecules, compositions and methods for producing said antibodymolecules.

BACKGROUND OF THE INVENTION

Programmed Death 1 (PD-1), also known as CD279; gene name PDCD1;accession number NP_(—)005009 is a cell surface receptor with a criticalrole in regulating the balance between stimulatory and inhibitorysignals in the immune system and maintaining peripheral tolerance(Ishida, Y et al. 1992 EMBO J 11 3887; Kier, Mary E et al. 2008 Annu RevImmunol 26 677-704; Okazaki, Taku et al. 2007 International Immunology19 813-824). It is an inhibitory member of the immunoglobulinsuper-family with homology to CD28. The structure of PD-1 is a monomerictype 1 transmembrane protein, consisting of one immunoglobulinvariable-like extracellular domain and a cytoplasmic domain containingan immunoreceptor tyrosine-based inhibitory motif (ITIM) and animmunoreceptor tyrosine-based switch motif (ITSM). Expression of PD-1 isinducible on T cells, B cells, natural killer (NK) cells and monocytes,for example upon lymphocyte activation via T cell receptor (TCR) or Bcell receptor (BCR) signaling (Kier, Mary E et al. 2008 Annu Rev Immunol26 677-704; Agata, Y et al 1996 Int Immunol 8 765-72). PD-1 has twoknown ligands, PD-L1 (B7-H1, CD274) and PD-L2 (B7-DC, CD273), which arecell surface expressed members of the B7 family (Freeman, Gordon et al.2000 J Exp Med 192 1027; Latchman, Y et al. 2001 Nat Immunol 2 261).Upon ligand engagement, PD-1 recruits phosphatases such as SHP-1 andSHP-2 to its intracellular tyrosine motifs which subsequentlydephosphorylate effector molecules activated by TCR or BCR signaling(Chemnitz, J et al. 2004 J Immunol 173 945-954; Riley, James L 2009Immunological Reviews 229 114-125) In this way, PD-1 transducesinhibitory signals into T and B cells only when it is engagedsimultaneously with the TCR or BCR.

PD-1 has been demonstrated to down-regulate effector T cell responsesvia both cell-intrinsic and cell-extrinsic functional mechanisms.Inhibitory signaling through PD-1 induces a state of anergy orunresponsiveness in T cells, resulting in the cells being unable toclonally expand or produce optimal levels of effector cytokines. PD-1may also induce apoptosis in T cells via its ability to inhibit survivalsignals from co-stimulation, which leads to reduced expression of keyanti-apoptotic molecules such as Bcl-_(XL) (Kier, Mary E et al. 2008Annu Rev Immunol 26 677-704). In addition to these direct effects,recent publications have implicated PD-1 as being involved in thesuppression of effector cells by promoting the induction and maintenanceof regulatory T cells (T_(REG)). For example, PD-L1 expressed ondendritic cells was shown to act in synergy with TGF-β to promote theinduction of CD4⁺ FoxP3⁺ T_(REG) with enhanced suppressor function(Francisco, Loise M et al. 2009 J Exp Med 206 3015-3029).

The first indication of the importance of PD-1 in peripheral toleranceand inflammatory disease came from the observation that PD-1 knockout(Pdcd1^(−/−)) mice develop spontaneous autoimmunity. Fifty percent ofPdcd1^(−/−) mice on a C57BL/6 background develop lupus-likeglomerulonephritis and arthritis by 14 months of age andBALB/c-Pdcd1^(−/−) mice develop a fatal dilated cardiomyopathy andproduction of autoantibodies against cardiac troponin I from 5 weeksonwards (Nishimura, H et al. 1999 Immunity 11 141-151; Nishimura, H etal. 2001 Science 291 319-322). Furthermore, introduction of PD-1deficiency to the non-obese diabetic (NOD) mouse strain dramaticallyaccelerates the onset and incidence of diabetes resulting in allNOD-Pdcd1^(−/−) mice developing diabetes by 10 weeks of age (Wang, J etal. 2005 Proc Natl Acad Sci USA 102 11823). Additionally, using inducedmurine models of autoimmunity such as experimental autoimmuneencephalomyelitis (EAE), or transplantation/graft-versus-host (GVHD)models, several groups have shown that blocking the PD-1-PD-Linteraction exacerbates disease, further confirming the key role of PD-1in inflammatory diseases. Importantly, evidence suggests that PD-1 has acomparable immune modulatory function in humans as mice, aspolymorphisms in human PDCD1 have been associated with a range ofautoimmune diseases including systemic lupus erythematosus (SLE),multiple sclerosis (MS), type I diabetes (TID), rheumatoid arthritis(RA) and Grave's disease (Okazaki, Taku et al. 2007 InternationalImmunology 19 813-824; Prokunina, L et al. 2002 Nat Genet 32 666-669;Kroner, A et al. 2005 Ann Neurol 58 50-57; Prokunina, L et al 2004Arthritis Rheum 50 1770).

Several therapeutic approaches to enhance PD-1 signaling and modulateinflammatory disease have been reported, using murine models ofautoimmunity. One such approach tried was to generate artificialdendritic cells which over-express PD-L1. Injection of mice withantigen-loaded PD-L1-dendritic cells before or after induction of EAE byMOG peptide immunisation reduced the inflammation of the spinal cord aswell as the clinical severity of the disease (Hirata, S et al. 2005 JImmunol 174 1888-1897). Another approach was to try to cure lupus-likesyndrome in BXSB mice by delivering a PD-1 signal using a recombinantadenovirus expressing mouse PD-L1. Injection of this virus partiallyprevented the development of nephritis as shown by lower frequency ofproteinuria, reduced serum anti-dsDNA Ig and better renal pathology(Ding, H et al. 2006 Clin Immunol 118 258). These results suggest thatenhancing the PD-1 signal could have therapeutic benefit in humanautoimmune disease. An alternative therapeutic approach more appropriateas a human drug treatment would be to use an agonistic monoclonalantibody against human PD-1. Binding of this agonistic antibody wouldideally independently transduce inhibitory signals through PD-1 whilstalso synergising with ongoing endogenous signals emanating from thenatural PD-1-PD1-L interaction. An agonistic anti-PD-1 mAb would bepredicted to modulate a range of immune cell types involved ininflammatory disease including T cells, B cells, NK cells and monocytesand would therefore have utility in the treatment of a wide range ofhuman autoimmune or inflammatory disorders.

Whilst a number of antagonistic anti-PD-1 antibodies have beendescribed, to date the only PD-1 agonistic antibodies described in theliterature, to the best of the inventors knowledge, still also block thePD-1-PD1L and PD1-PD2L interaction. See for Example, WO2004/056875.

Accordingly there is still a need in the art for improved agonisticanti-PD-1 antibodies suitable for treating patients, in particular thosewhich do not block the PD1-PDL1 or the PD1-PDL2 interaction.

We have now identified high affinity agonistic anti-PD-1 antibodiessuitable for use in the treatment or prophylaxis of immune disorders,for example by reducing the T cell response. Non limiting examples ofimmune disorders that can be treated via the administration of PD-1specific antibodies to a subject include, but are not limited to,rheumatoid arthritis, multiple sclerosis, inflammatory bowel disease,Crohn's disease, systemic lupus erythematosus, type I diabetes,transplant rejection, graft-versus-host disease, hyperproliferativeimmune disorders, cancer and infectious diseases.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows amino acid sequences relating to antibody 949 according tothe disclosure

FIGS. 2-12 shows certain amino acid or DNA sequences relating to anantibody according to the disclosure

FIG. 13 shows Inhibition of human CD4⁺ T cell proliferation by antibody949.

FIG. 14 Ligand blocking assay with antibody 949 and humanised versions.

FIG. 15 Stimulation of SEAP from the human PD-1/CD28/Zeta reporter cellline by antibody 949.

FIG. 16 Species Cross-reactivity of 949 chimeric and humanised graftswith PD-1

FIG. 17 shows an alignment of the light chains for the murine, acceptorframeworks and humanised light chains.

FIG. 18 shows an alignment of the heavy chains for the murine, acceptorframeworks and humanised heavy chains.

FIG. 19 shows an amino acid sequence of a heavy chain of antibody 949 ina huIgG4 format

FIG. 20 shows a nucleic acid sequence of a heavy chain of antibody 949in a huIgG4 format

FIG. 21 shows an amino acid sequence of a heavy chain, including thesignal sequence, of antibody 949 in a huIgG4 format

FIG. 22 shows a nucleic acid sequence of a heavy chain, including thesignal sequence, of antibody 949 in a huIgG4 format

FIG. 23 shows an amino acid sequence of a heavy chain of antibody 949 ina huIgG1 format

FIG. 24 shows a nucleic acid sequence of a heavy chain of antibody 949in a huIgG1 format

FIG. 25 shows an amino acid sequence of a heavy chain, including thesignal sequence, of antibody 949 in a huIgG1 format

FIG. 26 shows a nucleic acid sequence of a heavy chain, including thesignal sequence, of antibody 949 in a huIgG1 format

FIGS. 27 to 30 show various amino acid or nucleotide sequences for avariable region wherein CDR3 has been amended to remove a deamidationsite.

FIGS. 31 to 38 show various amino acid or nucleotide sequences for avariable region, and variable region plus constant region.

FIG. 39 shows the results of PD-1 ligand blocking binding assay.

FIGS. 40 and 41 shows activated T-cell binding assay with variousconstructs

FIGS. 42 a) and b) show the cross-reactivity of various antibodyconstructs with human PD-1 and cyno PD-1

FIG. 43 shows an alignment of the light chains for the murine, acceptorframeworks and humanised light chains

DETAILED DESCRIPTION OF THE INVENTION

The parental murine antibody hybridoma from which the humanisedantibodies are derived is referred to herein as Clone 19. The clonedrecombinant antibody derived from Clone 19 is referred to herein asantibody CA051_(—)00949 also referred to herein as 949.

The residues in antibody variable domains are conventionally numberedaccording to a system devised by Kabat et al. This system is set forthin Kabat et al., 1987, in Sequences of Proteins of ImmunologicalInterest, US Department of Health and Human Services, NIH, USA(hereafter “Kabat et al. (supra)”). This numbering system is used in thepresent specification except where otherwise indicated.

The Kabat residue designations do not always correspond directly withthe linear numbering of the amino acid residues. The actual linear aminoacid sequence may contain fewer or additional amino acids than in thestrict Kabat numbering corresponding to a shortening of, or insertioninto, a structural component, whether framework or complementaritydetermining region (CDR), of the basic variable domain structure. Thecorrect Kabat numbering of residues may be determined for a givenantibody by alignment of residues of homology in the sequence of theantibody with a “standard” Kabat numbered sequence.

The CDRs of the heavy chain variable domain are located at residues31-35 (CDR-H1), residues 50-65 (CDR-H2) and residues 95-102 (CDR-H3)according to the Kabat numbering system. However, according to Chothia(Chothia, C. and Lesk, A. M. J. Mol. Biol., 196, 901-917 (1987)), theloop equivalent to CDR-H1 extends from residue 26 to residue 32. Thusunless indicated otherwise ‘CDR-H1’ as employed herein is intended torefer to residues 26 to 35, as described by a combination of the Kabatnumbering system and Chothia's topological loop definition.

The CDRs of the light chain variable domain are located at residues24-34 (CDR-L1), residues 50-56 (CDR-L2) and residues 89-97 (CDR-L3)according to the Kabat numbering system.

As used herein, the term ‘agonistic antibody’ describes an antibody thatis capable of stimulating the biological signaling activity of PD-1,leading to phosphatase recruitment to its intracellular domain and henceinactivation of T or B cell receptor signaling and phenotypiccharacteristics associated with activation.

Antibodies for use in the present invention may be obtained using anysuitable method known in the art. The PD-1 polypeptide/protein includingfusion proteins, for example PD-1-Fc fusions proteins or cells(recombinantly or naturally) expressing the polypeptide (such asactivated T cells) can be used to produce antibodies which specificallyrecognise PD-1. The PD-1 polypeptide may be the ‘mature’ polypeptide ora biologically active fragment or derivative thereof. Suitably the PD-1polypeptide is the mature human polypeptide or the extracellular domainor fragment thereof. The extracellular domain typically comprises aminoacids 21-170 of the PD-1 protein (SWISS PROT entry Q15116). PD-1polypeptides may be prepared by processes well known in the art fromgenetically engineered host cells comprising expression systems or theymay be recovered from natural biological sources. In the presentapplication, the term “polypeptides” includes peptides, polypeptides andproteins. These are used interchangeably unless otherwise specified. ThePD-1 polypeptide may in some instances be part of a larger protein suchas a fusion protein for example fused to an affinity tag. Antibodiesgenerated against the PD-1 polypeptide may be obtained, whereimmunisation of an animal is necessary, by administering thepolypeptides to an animal, preferably a non-human animal, usingwell-known and routine protocols, see for example Handbook ofExperimental Immunology, D. M. Weir (ed.), Vol 4, Blackwell ScientificPublishers, Oxford, England, 1986). Many warm-blooded animals, such asrabbits, mice, rats, sheep, cows, camels or pigs may be immunized.However, mice, rabbits, pigs and rats are generally most suitable.

Monoclonal antibodies may be prepared by any method known in the artsuch as the hybridoma technique (Kohler & Milstein, 1975, Nature,256:495-497), the trioma technique, the human B-cell hybridoma technique(Kozbor et al., 1983, Immunology Today, 4:72) and the EBV-hybridomatechnique (Cole et al., Monoclonal Antibodies and Cancer Therapy, pp77-96, Alan R Liss, Inc., 1985).

Antibodies for use in the invention may also be generated using singlelymphocyte antibody methods by cloning and expressing immunoglobulinvariable region cDNAs generated from single lymphocytes selected for theproduction of specific antibodies by, for example, the methods describedby Babcook, J. et al., 1996, Proc. Natl. Acad. Sci. USA93(15):7843-78481; WO92/02551; WO2004/051268 and International PatentApplication number WO2004/106377.

Screening for antibodies can be performed using assays to measurebinding to human PD-1 and/or assays to measure the ability to agonisePD1 activity. An example of a binding assay is an ELISA, in particular,using a fusion protein of human PD-1 and human Fc, which is immobilizedon plates, and employing a conjungated secondary antibody to detectanti-PD-1 antibody bound to the fusion protein. Examples of suitableagonism and ligand blocking assays are described in the Examples herein.

Humanised antibodies (which include CDR-grafted antibodies) are antibodymolecules having one or more complementarity determining regions (CDRs)from a non-human species and a framework region from a humanimmunoglobulin molecule (see, e.g. U.S. Pat. No. 5,585,089; WO91/09967).It will be appreciated that it may only be necessary to transfer thespecificity determining residues of the CDRs rather than the entire CDR(see for example, Kashmiri et al., 2005, Methods, 36, 25-34). Humanisedantibodies may optionally further comprise one or more frameworkresidues derived from the non-human species from which the CDRs werederived.

The present invention provides agonistic humanised antibodies havingspecificity for human PD-1.

An agonistic murine anti-PD-1 antibody (Clone 19) was described inPCT/IB2009/06940 (unpublished) and the sequences of the variable regionsand CDRs of this antibody are provided in FIG. 1. In particular the CDRsof this antibody are provided in FIG. 1( c), SEQ ID NOs 1-6.

An improved version of the CDRL3 (SEQ ID NO:6) derived from Clone 19 isprovided in FIG. 2( a) (SEQ ID NO:7) in which a potential deamidationsite has been modified. Accordingly, in one embodiment the presentinvention provides a humanised agonistic antibody which binds human PD-1comprising a heavy chain and a light chain wherein the variable domainof the heavy chain comprises the sequence given in SEQ ID NO:1 forCDR-H1, the sequence given in SEQ ID NO:2 for CDR-H2 and the sequencegiven in SEQ ID NO:3 for CDR-H3 and the variable domain of the lightchain comprises the sequence given in SEQ ID NO:4 for CDR-L1, thesequence given in SEQ ID NO:5 for CDR-L2 and the sequence given in SEQID NO:7 for CDR-L3.

As used herein, the term ‘humanised antibody molecule’ refers to anantibody molecule wherein the heavy and/or light chain contains one ormore CDRs (including, if desired, one or more modified CDRs) from adonor antibody (e.g. a murine monoclonal antibody) grafted into a heavyand/or light chain variable region framework of an acceptor antibody(e.g. a human antibody). For a review, see Vaughan et al, NatureBiotechnology, 16, 535-539, 1998. In one embodiment rather than theentire CDR being transferred, only one or more of the specificitydetermining residues from any one of the CDRs described herein above aretransferred to the human antibody framework (see for example, Kashmiriet al., 2005, Methods, 36, 25-34). In one embodiment only thespecificity determining residues from one or more of the CDRs describedherein above are transferred to the human antibody framework. In anotherembodiment only the specificity determining residues from each of theCDRs described herein above are transferred to the human antibodyframework.

When the CDRs or specificity determining residues are grafted, anyappropriate acceptor variable region framework sequence may be usedhaving regard to the class/type of the donor antibody from which theCDRs are derived, including mouse, primate and human framework regions.Suitably, the Humanised antibody according to the present invention hasa variable domain comprising human acceptor framework regions as well asone or more of the CDRs provided in FIG. 1( c) or FIG. 2( a). Thus,provided in one embodiment is an agonistic humanised antibody whichbinds human PD-1 wherein the variable domain comprises human acceptorframework regions and non-human donor CDRs.

Examples of human frameworks which can be used in the present inventionare KOL, NEWM, REI, EU, TUR, TEI, LAY and POM (Kabat et al., supra). Forexample, KOL and NEWM can be used for the heavy chain, REI can be usedfor the light chain and EU, LAY and POM can be used for both the heavychain and the light chain. Alternatively, human germline sequences maybe used; these are available at: http://vbase.mrc-cpe.cam.ac.uk/

In a humanised antibody of the present invention, the acceptor heavy andlight chains do not necessarily need to be derived from the sameantibody and may, if desired, comprise composite chains having frameworkregions derived from different chains.

Once such suitable framework region for the heavy chain of the humanisedantibody of the present invention is derived from the human sub-groupVH1 sequence 1-3 1-46 together with JH4 (SEQ ID NO:52). Accordingly, inone example there is provided an agonistic humanised antibody comprisingthe sequence given in SEQ ID NO:1 for CDR-H1, the sequence given in SEQID NO:2 for CDR-H2 and the sequence given in SEQ ID NO:3 for CDRH3wherein the heavy chain framework region is derived from the humansubgroup VH1 sequence 1-3 1-46 together with JH4. The sequence of humanJH4 is as follows: (YFDY)WGQGTLVTVS (Seq ID No: 56). The YFDY motif ispart of CDR-H3 and is not part of framework 4 (Ravetch, J V. et al.,1981, Cell, 27, 583-591).

Another suitable framework region for the heavy chain of the humanisedantibody of the present invention is derived from the human sub-groupVH1 sequence 1-2 1-e together with JH4 (SEQ ID NO:54). Accordingly, inone example there is provided an agonistic humanised antibody comprisingthe sequence given in SEQ ID NO:1 for CDR-H1, the sequence given in SEQID NO:2 for CDR-H2 and the sequence given in SEQ ID NO:3 for CDRH3wherein the heavy chain framework region is derived from the humansubgroup VH1 sequence 1-2 1-e together with JH4, see for example SEQ IDNO:46). The sequence of human JH4 is as follows: (YFDY)WGQGTLVTVS (SeqID No: 56). The YFDY motif is part of CDR-H3 and is not part offramework 4 (Ravetch, J V. et al., 1981, Cell, 27, 583-591). In oneexample the heavy chain variable domain of the antibody comprises thesequence given in SEQ ID NO:46.

A suitable framework region for the light chain of the humanisedantibody of the present invention is derived from the human germlinesub-group VK1 sequence 2-1-(1) L23 together with JK4 (SEQ ID NO:48).Accordingly, in one example there is provided an agonistic humanisedantibody comprising the sequence given in SEQ ID NO:4 for CDR-L1, thesequence given in SEQ ID NO:5 for CDR-L2 and the sequence given in SEQID NO:6 or SEQ ID NO:7 for CDRL3 wherein the light chain frameworkregion is derived from the human subgroup sequence 2-1-(1) L23 togetherwith JK4. The JK4 sequence is as follows: (LT)FGGGTKVEIK (Seq ID No:57). The LT motif is part of CDR-L3 and is not part of framework 4(Hieter, P A., et al., 1982, J. Biol. Chem., 257, 1516-1522).

Another suitable framework region for the light chain of the humanisedantibody of the present invention is derived from the human germlinesub-group VK3 sequence 6-1-(1) A27 together with JK4 (SEQ ID NO:50).Accordingly, in one example there is provided an agonistic humanisedantibody comprising the sequence given in SEQ ID NO:4 for CDR-L1, thesequence given in SEQ ID NO:5 for CDR-L2 and the sequence given in SEQID NO:6 or SEQ ID NO:7 for CDRL3 wherein the light chain frameworkregion is derived from the human subgroup sequence VK3 6-1-(1) A27together with JK4. The JK4 sequence is as follows: (LT)FGGGTKVEIK (SeqID No: 57). The LT motif is part of CDR-L3 and is not part of framework4 (Hieter, P A., et al., 1982, J. Biol. Chem., 257, 1516-1522).

Also, in a humanised antibody of the present invention, the frameworkregions need not have exactly the same sequence as those of the acceptorantibody. For instance, unusual residues may be changed to morefrequently-occurring residues for that acceptor chain class or type.Alternatively, selected residues in the acceptor framework regions maybe changed so that they correspond to the residue found at the sameposition in the donor antibody (see Reichmann et al., 1998, Nature, 332,323-324). Such changes should be kept to the minimum necessary torecover the affinity of the donor antibody. A protocol for selectingresidues in the acceptor framework regions which may need to be changedis set forth in WO 91/09967.

Suitably, in a humanised antibody molecule of the present invention, ifthe acceptor heavy chain has the human VH1 sequence 1-3 1-46 togetherwith JH4, then the acceptor framework regions of the heavy chaincomprise, in addition to the three donor CDRs (SEQ ID NOs:1, 2 and 3), adonor residue at at least one of positions 25, 37, 41, 48, 71, 73 and 76(according to Kabat et al., (supra)). Accordingly, in one example thereis provided a humanised antibody, wherein at least the residues at eachof positions 25, 37, 41, 48, 71, 73 and 76 of the variable domain of theheavy chain are donor residues, see for example the sequence given inSEQ ID NO:30. In one example there is provided a humanised antibody,wherein at least the residues at each of positions 25, 37, 41 and 48 ofthe variable domain of the heavy chain are donor residues, see forexample the sequence given in SEQ ID NO:38. In one example there isprovided a humanised antibody, wherein at least the residue at position25 of the variable domain of the heavy chain is a donor residue, see forexample the sequence given in SEQ ID NO: 40.

Suitably, in a humanised antibody molecule of the present invention, ifthe acceptor heavy chain has the human VH1 sequence 1-2 1-e togetherwith JH4, then the acceptor framework regions of the heavy chaincomprise, in addition to the three donor CDRs (SEQ ID NOs:1, 2 and 3), adonor residue at at least one of positions 25, 37, 41, 48, 71, 76 and 78(according to Kabat et al., (supra)). Accordingly, in one example thereis provided a humanised antibody, wherein at least the residues at eachof positions 25, 37, 41, 48, 71, 76 and 78 of the variable domain of theheavy chain are donor residues, see for example the sequence given inSEQ ID NO:42. In one example there is provided a humanised antibody,wherein at least the residues at each of positions 25, 37, 41 and 48 ofthe variable domain of the heavy chain are donor residues, see forexample the sequence given in SEQ ID NO:44.

Suitably, in a humanised antibody molecule according to the presentinvention, if the acceptor light chain has the human sub-group VK1sequence 2-1-(1) L23 together with JK4, then the acceptor frameworkregions of the light chain comprise, in addition to three donor CDRs(SEQ ID NOs:4, 5 and 6 or 7), a donor residue at at least one ofpositions 1, 2, 3, 4, 47, 60 and 70. Accordingly, in one example thereis provided a humanised antibody, wherein at least the residues at eachof positions 1, 2, 3, 4, 47, 60 and 70 of the variable domain of thelight chain are donor residues, see for example SEQ ID NO:10. In oneexample there is provided a humanised antibody, wherein at least theresidues at each of positions 1, 2, 3, and 4 of the variable domain ofthe light chain are donor residues, see for example SEQ ID NO:18 or SEQID NO:20. In one embodiment the antibody comprises a sequence as shownin SEQ ID NO. 66. In one example there is provided a humanised antibody,wherein at least the residues at each of positions 1, 2 and 3 of thevariable domain of the light chain are donor residues, see for exampleSEQ ID NO:22 or SEQ ID NO:24.

Suitably, in a humanised antibody molecule according to the presentinvention, if the acceptor light chain has the human sub-group VK3sequence 6-1-(1) A27 together with JK4, then the acceptor frameworkregions of the light chain comprise, in addition to the three donor CDRs(SEQ ID NOs:4, 5 and 6 or 7), a donor residue at at least one ofpositions 2, 47, 58, 70, 71 and 85. Accordingly, in one example there isprovided a humanised antibody, wherein at least the residues at each ofpositions 2, 47, 58, 70, 71 and 85 of the variable domain of the lightchain are donor residues, see for example, SEQ ID NO:26 or SEQ ID NO:28.

Donor residues are residues from the donor antibody, i.e. the antibodyfrom which the CDRs were originally derived. Donor residues may replacehuman acceptor framework residues (acceptor residues) at one or more ofthe positions listed below.

VK1 Light chain 2-1(1) L23 Kabat position Human acceptor residue 1Alanine 2 Isoleucine 3 Arginine 4 Methionine 47 Phenylalanine 60 Serine70 Aspartic acid

VK3 Light chain 6-1-(1) A27 Kabat position Human acceptor residue 2Isoleucine 47 Leucine 58 Isoleucine 70 Aspartic acid 71 Phenylalanine 85Valine

VH1 Heavy chain 1-3 1-46 Kabat position Human acceptor residue 25 Serine37 Valine 41 Proline 48 Methionine 71 Arginine 73 Threonine 76 Serine

VH1 Heavy chain 1-2 1-e Kabat position Human acceptor residue 25 Serine37 Valine 41 Proline 48 Methionine 71 Alanine 76 Serine 78 Alanine

The antibody molecules of the present invention suitably comprise acomplementary light chain or a complementary heavy chain, respectively.Accordingly, in one embodiment the present invention provides ahumanised agonistic antibody which binds human PD-1 having a heavy chaincomprising a sequence selected from the group consisting of: SEQ IDNO:30, SEQ ID NO:38, SEQ ID NO:40, SEQ ID NO:42, SEQ ID NO:44 and SEQ IDNO:46 and a light chain comprising a sequence selected from the groupconsisting of SEQ ID NO: 10, SEQ ID NO:18, SEQ ID NO:20, SEQ ID NO:22,SEQ ID NO:24, SEQ ID NO:26 and SEQ ID NO:28.

The antibody molecules of the present invention suitably comprise acomplementary light chain or a complementary heavy chain, respectively.Accordingly, in one embodiment the present invention provides ahumanised agonistic antibody which binds human PD-1 having a heavy chaincomprising a sequence selected from the group consisting of: SEQ IDNO:30, SEQ ID NO:38, SEQ ID NO:40, SEQ ID NO:42, SEQ ID NO:44 and SEQ IDNO:46 and a light chain comprising a sequence selected from the groupconsisting of SEQ ID NO: 10, SEQ ID NO:18, SEQ ID NO:20, SEQ ID NO:22,SEQ ID NO:24, SEQ ID NO:26, SEQ ID NO:28 and SEQ ID NO:66.

In one embodiment the heavy chain comprises a sequence selected from SEQID NO: 30 and SEQ ID NO: 46 and the light chain comprises a sequenceaccording to SEQ ID NO: 66.

It will be appreciated that one or more amino acid substitutions,additions and/or deletions may be made to the CDRs or other sequences(e.g variable domains) provided by the present invention withoutsignificantly altering the ability of the antibody to bind to PD-1 andto agonise PD-1 activity. The effect of any amino acid substitutions,additions and/or deletions can be readily tested by one skilled in theart, for example by using the methods described herein, in particular inthe Examples, to determine PD-1 binding and PD-1 agonism.

In another embodiment, an antibody of the present invention comprises aheavy chain, wherein the variable domain of the heavy chain comprises asequence having at least 60% identity or similarity to the sequencegiven in any one of SEQ ID NO:30, SEQ ID NO:38, SEQ ID NO:40, SEQ IDNO:42, SEQ ID NO:44 or SEQ ID NO:46. In one embodiment, an antibody ofthe present invention comprises a heavy chain, wherein the variabledomain of the heavy chain comprises a sequence having at least 70%, 80%,90%, 95% or 98% identity or similarity to the sequence given in any oneof SEQ ID NO:30, SEQ ID NO:38, SEQ ID NO:40, SEQ ID NO:42, SEQ ID NO:44or SEQ ID NO:46.

“Identity”, as used herein, indicates that at any particular position inthe aligned sequences, the amino acid residue is identical between thesequences. “Similarity”, as used herein, indicates that, at anyparticular position in the aligned sequences, the amino acid residue isof a similar type between the sequences. For example, leucine may besubstituted for isoleucine or valine. Other amino acids which can oftenbe substituted for one another include but are not limited to:

-   phenylalanine, tyrosine and tryptophan (amino acids having aromatic    side chains);-   lysine, arginine and histidine (amino acids having basic side    chains);-   aspartate and glutamate (amino acids having acidic side chains);-   asparagine and glutamine (amino acids having amide side chains); and    -   cysteine and methionine (amino acids having sulphur-containing        side chains). Degrees of identity and similarity can be readily        calculated (Computational Molecular Biology, Lesk, A. M., ed.,        Oxford University Press, New York, 1988; Biocomputing.        Informatics and Genome Projects, Smith, D. W., ed., Academic        Press, New York, 1993; Computer Analysis of Sequence Data, Part        1, Griffin, A. M., and Griffin, H. G., eds., Humana Press, New        Jersey, 1994; Sequence Analysis in Molecular Biology, von        Heinje, G., Academic Press, 1987, Sequence Analysis Primer,        Gribskov, M. and Devereux, J., eds., M Stockton Press, New York,        1991, the BLAST™ software available from NCBI (Altschul, S. F.        et al., 1990, J. Mol. Biol. 215:403-410; Gish, W. &        States, D. J. 1993, Nature Genet. 3:266-272. Madden, T. L. et        al., 1996, Meth. Enzymol. 266:131-141; Altschul, S. F. et al.,        1997, Nucleic Acids Res. 25:3389-3402; Zhang, J. & Madden, T. L.        1997, Genome Res. 7:649-656,).

In another embodiment, an antibody of the present invention comprises alight chain, wherein the variable domain of the light chain comprises asequence having at least 60% identity or similarity to the sequencegiven in any one of SEQ ID NO: 10, SEQ ID NO:18, SEQ ID NO:20, SEQ IDNO:22, SEQ ID NO:24, SEQ ID NO:26 or SEQ ID NO:28

In one embodiment the antibody of the present invention comprises alight chain, wherein the variable domain of the light chain comprises asequence having at least 70%, 80%, 90%, 95% or 98% identity orsimilarity to the sequence given in any one of SEQ ID NO: 10, SEQ IDNO:18, SEQ ID NO:20, SEQ ID NO:22, SEQ ID NO:24, SEQ ID NO:26 or SEQ IDNO:28.

In one embodiment the antibody of the present invention comprises asequence having at least 70%, 80%, 90%, 95% or 98% identity orsimilarity to the sequence given herein, for example SEQ ID NO:66 or SEQID NO:70.

In one embodiment the antibody of the present invention comprises asequence having at least 70%, 80%, 90%, 95% or 98% identity orsimilarity to the sequence given herein, for example SEQ ID NO: 34, SEQID NO:58, SEQ ID NO:62, SEQ ID NO:76 or SEQ ID NO:80.

In another embodiment of the invention, the antibody comprises a heavychain and a light chain, wherein the variable domain of the heavy chaincomprises a sequence having at least 60% identity or similarity to thesequence given in any one of SEQ ID NO:30, SEQ ID NO:38, SEQ ID NO:40,SEQ ID NO:42, SEQ ID NO:44 or SEQ ID NO:46 and the variable domain ofthe light chain comprises a sequence having at least 60% identity orsimilarity to the sequence given in any one of SEQ ID NO: 10, SEQ IDNO:18, SEQ ID NO:20, SEQ ID NO:22, SEQ ID NO:24, SEQ ID NO:26 or SEQ IDNO:28.

Suitably, the antibody comprises a heavy chain, wherein the variabledomain of the heavy chain comprises a sequence having at least 70%, 80%,90%, 95% or 98% identity or similarity to the sequence given in any oneof SEQ ID NO:30, SEQ ID NO:38, SEQ ID NO:40, SEQ ID NO:42, SEQ ID NO:44or SEQ ID NO:46 and a light chain, wherein the variable domain of thelight chain comprises a sequence having at least 70%, 80%, 90%, 95% or98% identity or similarity to the sequence given in any one of SEQ IDNO: 10, SEQ ID NO:18, SEQ ID NO:20, SEQ ID NO:22, SEQ ID NO:24, SEQ IDNO:26 or SEQ ID NO:28.

In another embodiment of the invention, the antibody comprises a heavychain and a light chain, wherein the variable domain of the heavy chaincomprises a sequence having at least 60% identity or similarity to thesequence given in any one of SEQ ID NO:30, SEQ ID NO:38, SEQ ID NO:40,SEQ ID NO:42, SEQ ID NO:44, SEQ ID NO:46, SEQ ID NO: 58, SEQ ID NO: 62,SEQ ID NO:76 or SEQ ID NO:80 and the variable domain of the light chaincomprises a sequence having at least 60% identity or similarity to thesequence given in any one of SEQ ID NO: 10, SEQ ID NO:18, SEQ ID NO:20,SEQ ID NO:22, SEQ ID NO:24, SEQ ID NO:26, SEQ ID NO:28, SEQ ID NO:66 orSEQ ID NO:70.

Suitably, the antibody comprises a heavy chain, wherein the variabledomain of the heavy chain comprises a sequence having at least 70%, 80%,90%, 95% or 98% identity or similarity to the sequence given in any oneof SEQ ID NO:30, SEQ ID NO:38, SEQ ID NO:40, SEQ ID NO:42, SEQ ID NO:44,SEQ ID NO:46, SEQ ID NO: 58, SEQ ID NO: 62, SEQ ID NO:76 or SEQ ID NO:80and a light chain, wherein the variable domain of the light chaincomprises a sequence having at least 70%, 80%, 90%, 95% or 98% identityor similarity to the sequence given in any one of SEQ ID NO: 10, SEQ IDNO:18, SEQ ID NO:20, SEQ ID NO:22, SEQ ID NO:24, SEQ ID NO:26, SEQ IDNO:28, SEQ ID NO: 66 or SEQ ID NO: 70.

The antibody molecules of the present invention may comprise a completeantibody molecule having full length heavy and light chains or afragment thereof and may be, but are not limited to Fab, modified Fab,Fab′, modified Fab′, F(ab)₂, Fv, single domain antibodies (e.g. VH or VLor VHH), scFv, bi, tri or tetra-valent antibodies, Bis-scFv, diabodies,triabodies, tetrabodies and epitope-binding fragments of any of theabove (see for example Holliger and Hudson, 2005, Nature Biotech.23(9):1126-1136; Adair and Lawson, 2005, Drug Design Reviews—Online2(3), 209-217). The methods for creating and manufacturing theseantibody fragments are well known in the art (see for example Verma etal., 1998, Journal of Immunological Methods, 216, 165-181). Otherantibody fragments for use in the present invention include the Fab andFab′ fragments described in International patent applicationsWO2005/003169, WO2005/003170 and WO2005/003171. Multi-valent antibodiesmay comprise multiple specificities e.g bispecific or may bemonospecific (see for example WO 92/22853, WO05/113605, WO2009/040562and WO2010/035012).

In one embodiment there is a provided a heavy chain selected from SEQ IDNO: 58, SEQ ID NO: 62, SEQ ID NO: 76 or SEQ ID NO:80 in combination witha light chain comprising SEQ ID NO: 66.

In one embodiment there is provided a heavy chain selected from SEQ IDNO: 58 in combination with a light chain comprising SEQ ID NO: 66.

In one embodiment there is provided a heavy chain selected from SEQ IDNO: 62 in combination with a light chain comprising SEQ ID NO: 66.

In one embodiment there is provided a heavy chain selected from SEQ IDNO: 76 in combination with a light chain comprising SEQ ID NO: 66.

In one embodiment there is provided a heavy chain selected from SEQ IDNO: 80 in combination with a light chain comprising SEQ ID NO: 66.

In one embodiment there is provided a heavy chain selected from SEQ IDNO: 58, SEQ ID NO: 62 or SEQ ID NO: 76 in combination with a light chainaccording to SEQ ID NO: 70.

In one embodiment there is provided a heavy chain selected from SEQ IDNO: 58 in combination with a light chain according to SEQ ID NO: 70.

In one embodiment there is provided a heavy chain selected from SEQ IDNO: 62 or in combination with a light chain according to SEQ ID NO: 70.

In one embodiment there is provided a heavy chain selected from SEQ IDNO: 76 in combination with a light chain according to SEQ ID NO: 70.

In one embodiment there is provided a heavy chain selected from SEQ IDNO: 80 in combination with a light chain according to SEQ ID NO: 70.

In one embodiment the antibody according to the present disclosure isprovided as PD-1 binding antibody fusion protein which comprises animmunoglobulin moiety, for example a Fab or Fab′ fragment, and one ortwo single domain antibodies (dAb) linked directly or indirectlythereto, for example as described in WO2009/040562.

In one embodiment the fusion protein comprises two domain antibodies,for example as a variable heavy (VH) and variable light (VL) pairing,optionally linked by a disulphide bond.

In one embodiment the Fab or Fab′ element of the fusion protein has thesame or similar specificity to the single domain antibody or antibodies.In one embodiment the Fab or Fab′ has a different specificity to thesingle domain antibody or antibodies, that is to say the fusion proteinis multivalent. In one embodiment a multivalent fusion protein accordingto the present invention has an albumin binding site, for example aVH/VL pair therein provides an albumin binding site.

The constant region domains of the antibody molecule of the presentinvention, if present, may be selected having regard to the proposedfunction of the antibody molecule, and in particular the effectorfunctions which may be required. For example, the constant regiondomains may be human IgA, IgD, IgE, IgG or IgM domains. In particular,human IgG constant region domains may be used, especially of the IgG1and IgG3 isotypes when the antibody molecule is intended for therapeuticuses and antibody effector functions are required. Alternatively, IgG2and IgG4 isotypes may be used when the antibody molecule is intended fortherapeutic purposes and antibody effector functions are not required,e.g. for simply agonising PD-1 activity. It will be appreciated thatsequence variants of these constant region domains may also be used. Forexample IgG4 molecules in which the serine at position 241 has beenchanged to proline as described in Angal et al., Molecular Immunology,1993, 30 (1), 105-108 may be used. It will also be understood by oneskilled in the art that antibodies may undergo a variety ofposttranslational modifications. The type and extent of thesemodifications often depends on the host cell line used to express theantibody as well as the culture conditions. Such modifications mayinclude variations in glycosylation, methionine oxidation,diketopiperazine formation, aspartate isomerization and asparaginedeamidation. A frequent modification is the loss of a carboxy-terminalbasic residue (such as lysine or arginine) due to the action ofcarboxypeptidases (as described in Harris, R J. Journal ofChromatography 705:129-134, 1995). Accordingly, the C-terminal lysine ofthe antibody heavy chain, for example as given in FIG. 8( a), SEQ ID NO:36, may be absent.

In one embodiment there is provided an antibody heavy chain comprisingor consisting of a sequence as per SEQ ID NO:58.

In one embodiment there is provided an antibody heavy chain comprisingor consisting of a sequence as per SEQ ID NO:62.

In one embodiment there is provided an antibody heavy chain comprisingor consisting of a sequence as per SEQ ID NO:76.

In one embodiment there is provided an antibody heavy chain comprisingor consisting of a sequence as per SEQ ID NO:80.

In one embodiment there is provided a light chain comprising orconsisting of a sequence as per SEQ ID NO: 70.

In one embodiment the antibody heavy chain comprises a CH1 domain andthe antibody light chain comprises a CL domain, either kappa or lambda.

Biological molecules, such as antibodies or fragments, contain acidicand/or basic functional groups, thereby giving the molecule a netpositive or negative charge. The amount of overall “observed” chargewill depend on the absolute amino acid sequence of the entity, the localenvironment of the charged groups in the 3D structure and theenvironmental conditions of the molecule. The isoelectric point (pI) isthe pH at which a particular molecule or solvent accessible surfacethereof carries no net electrical charge. In one example, the PD-1antibody and fragments of the invention may be engineered to have anappropriate isoelectric point. This may lead to antibodies and/orfragments with more robust properties, in particular suitable solubilityand/or stability profiles and/or improved purification characteristics.

Thus in one aspect the invention provides a humanised PD-1 antibodyengineered to have an isoelectric point, different to that of theoriginally identified antibody 949. The antibody may, for example beengineered by replacing an amino acid residue such as replacing anacidic amino acid residue with one or more basic amino acid residues.Alternatively, basic amino acid residues may be introduced or acidicamino acid residues can be removed. Alternatively, if the molecule hasan unacceptably high pI value acidic residues may be introduced to lowerthe pI, as required. It is important that when manipulating the pI caremust be taken to retain the desirable activity of the antibody orfragment. Thus in one embodiment the engineered antibody or fragment hasthe same or substantially the same activity as the “unmodified” antibodyor fragment.

Programs such as ** ExPASY http://www.expasy.ch/tools/pi_tool.html, andhttp://www.iut-arles.up.univ-mrs.fr/w3bb/d_abim/compo-p.html, may beused to predict the isoelectric point of the antibody or fragment.

The antibody molecules of the present invention suitably have a highbinding affinity, in particular nanomolar. Affinity may be measuredusing any suitable method known in the art, including BIAcore, asdescribed in the Examples herein, using isolated natural or recombinantPD-1 or a suitable fusion protein/polypeptide. In one example affinityis measured using recombinant human PD-1 extracellular domain asdescribed in the Examples herein. In one example the recombinant humanPD-1 extracellular domain used is a monomer. Suitably the antibodymolecules of the present invention have a binding affinity for isolatedhuman PD-1 of about 6 nM or better. In one embodiment the antibodymolecule of the present invention has a binding affinity of about 5 nMor better. In one embodiment the antibody molecule of the presentinvention has a binding affinity of about 4 nM or better. In oneembodiment the antibody molecule of the present invention has a bindingaffinity of about 3 nM or better. In one embodiment the presentinvention provides a humanised antibody with a binding affinity of about5 nM or better.

It will be appreciated that the affinity of antibodies provided by thepresent invention may be altered using any suitable method known in theart. The present invention therefore also relates to variants of theantibody molecules of the present invention, which have an improvedaffinity for PD-1. Such variants can be obtained by a number of affinitymaturation protocols including mutating the CDRs (Yang et al., J. Mol.Biol., 254, 392-403, 1995), chain shuffling (Marks et al.,Bio/Technology, 10, 779-783, 1992), use of mutator strains of E. coli(Low et al., J. Mol. Biol., 250, 359-368, 1996), DNA shuffling (Pattenet al., Curr. Opin. Biotechnol., 8, 724-733, 1997), phage display(Thompson et al., J. Mol. Biol., 256, 77-88, 1996) and sexual PCR(Crameri et al., Nature, 391, 288-291, 1998). Vaughan et al. (supra)discusses these methods of affinity maturation.

In one embodiment the antibody molecules of the present inventionagonise human PD-1 activity. Assays suitable for determining the abilityof an antibody to agonise PD-1 are described in the Examples herein. Ina preferred embodiment, the antibodies of the present invention do notblock the interaction between PD-1 and its ligand PD-1 L. Suitableassays for determining whether antibodies block PD-1 interaction withits ligand PD-1L are described in the examples herein (Freeman, Gordonet al. 2000 J Exp Med 192 1027; Butte, Mannish et al, 2007 Immunity27(1) 2007).

If desired an antibody for use in the present invention may beconjugated to one or more effector molecule(s). It will be appreciatedthat the effector molecule may comprise a single effector molecule ortwo or more such molecules so linked as to form a single moiety that canbe attached to the antibodies of the present invention. Where it isdesired to obtain an antibody fragment linked to an effector molecule,this may be prepared by standard chemical or recombinant DNA proceduresin which the antibody fragment is linked either directly or via acoupling agent to the effector molecule. Techniques for conjugating sucheffector molecules to antibodies are well known in the art (see,Hellstrom et al., Controlled Drug Delivery, 2nd Ed., Robinson et al.,eds., 1987, pp. 623-53; Thorpe et al., 1982, Immunol. Rev., 62:119-58and Dubowchik et al., 1999, Pharmacology and Therapeutics, 83, 67-123).Particular chemical procedures include, for example, those described inWO 93/06231, WO 92/22583, WO 89/00195, WO 89/01476 and WO 03/031581.Alternatively, where the effector molecule is a protein or polypeptidethe linkage may be achieved using recombinant DNA procedures, forexample as described in WO 86/01533 and EP0392745.

The term effector molecule as used herein includes, for example,antineoplastic agents, drugs, toxins, biologically active proteins, forexample enzymes, other antibody or antibody fragments, synthetic ornaturally occurring polymers, nucleic acids and fragments thereof e.g.DNA, RNA and fragments thereof, radionuclides, particularly radioiodide,radioisotopes, chelated metals, nanoparticles and reporter groups suchas fluorescent compounds or compounds which may be detected by NMR orESR spectroscopy.

Examples of effector molecules may include cytotoxins or cytotoxicagents including any agent that is detrimental to (e.g. kills) cells.Examples include combrestatins, dolastatins, epothilones, staurosporin,maytansinoids, spongistatins, rhizoxin, halichondrins, roridins,hemiasterlins, taxol, cytochalasin B, gramicidin D, ethidium bromide,emetine, mitomycin, etoposide, tenoposide, vincristine, vinblastine,colchicin, doxorubicin, daunorubicin, dihydroxy anthracin dione,mitoxantrone, mithramycin, actinomycin D, 1-dehydrotestosterone,glucocorticoids, procaine, tetracaine, lidocaine, propranolol, andpuromycin and analogs or homologs thereof.

Effector molecules also include, but are not limited to, antimetabolites(e.g. methotrexate, 6-mercaptopurine, 6-thioguanine, cytarabine,5-fluorouracil decarbazine), alkylating agents (e.g. mechlorethamine,thioepa chlorambucil, melphalan, carmustine (BSNU) and lomustine (CCNU),cyclothosphamide, busulfan, dibromomannitol, streptozotocin, mitomycinC, and cis-dichlorodiamine platinum (II) (DDP) cisplatin),anthracyclines (e.g. daunorubicin (formerly daunomycin) anddoxorubicin), antibiotics (e.g. dactinomycin (formerly actinomycin),bleomycin, mithramycin, anthramycin (AMC), calicheamicins orduocarmycins), and anti-mitotic agents (e.g. vincristine andvinblastine).

Other effector molecules may include chelated radionuclides such as¹¹¹In and ⁹⁰Y, Lu¹⁷⁷, Bismuth²¹³, Californium²⁵², Iridium¹⁹² andTungsten¹⁸⁸/Rhenium¹⁸⁸; or drugs such as but not limited to,alkylphosphocholines, topoisomerase I inhibitors, taxoids and suramin.Other effector molecules include proteins, peptides and enzymes. Enzymesof interest include, but are not limited to, proteolytic enzymes,hydrolases, lyases, isomerases, transferases. Proteins, polypeptides andpeptides of interest include, but are not limited to, immunoglobulins,toxins such as abrin, ricin A, pseudomonas exotoxin, or diphtheriatoxin, a protein such as insulin, tumour necrosis factor, α-interferon,β-interferon, nerve growth factor, platelet derived growth factor ortissue plasminogen activator, a thrombotic agent or an anti-angiogenicagent, e.g. angiostatin or endostatin, or, a biological responsemodifier such as a lymphokine, interleukin-1 (IL-1), interleukin-2(IL-2), granulocyte macrophage colony stimulating factor (GM-CSF),granulocyte colony stimulating factor (G-CSF), nerve growth factor (NGF)or other growth factor and immunoglobulins.

Other effector molecules may include detectable substances useful forexample in diagnosis. Examples of detectable substances include variousenzymes, prosthetic groups, fluorescent materials, luminescentmaterials, bioluminescent materials, radioactive nuclides, positronemitting metals (for use in positron emission tomography), andnonradioactive paramagnetic metal ions. See generally U.S. Pat. No.4,741,900 for metal ions which can be conjugated to antibodies for useas diagnostics. Suitable enzymes include horseradish peroxidase,alkaline phosphatase, beta-galactosidase, or acetylcholinesterase;suitable prosthetic groups include streptavidin, avidin and biotin;suitable fluorescent materials include umbelliferone, fluorescein,fluorescein isothiocyanate, rhodamine, dichlorotriazinylaminefluorescein, dansyl chloride and phycoerythrin; suitable luminescentmaterials include luminol; suitable bioluminescent materials includeluciferase, luciferin, and aequorin; and suitable radioactive nuclidesinclude ¹²⁵I, ¹³¹I, ¹¹¹In and ⁹⁹Tc.

In another example the effector molecule may increase the half-life ofthe antibody in vivo, and/or reduce immunogenicity of the antibodyand/or enhance the delivery of an antibody across an epithelial barrierto the immune system. Examples of suitable effector molecules of thistype include polymers, albumin, albumin binding proteins or albuminbinding compounds such as those described in WO05/117984.

Where the effector molecule is a polymer it may, in general, be asynthetic or a naturally occurring polymer, for example an optionallysubstituted straight or branched chain polyalkylene, polyalkenylene orpolyoxyalkylene polymer or a branched or unbranched polysaccharide, e.g.a homo- or hetero-polysaccharide.

Specific optional substituents which may be present on theabove-mentioned synthetic polymers include one or more hydroxy, methylor methoxy groups.

Specific examples of synthetic polymers include optionally substitutedstraight or branched chain poly(ethyleneglycol), poly(propyleneglycol)poly(vinylalcohol) or derivatives thereof, especially optionallysubstituted poly(ethyleneglycol) such as methoxypoly(ethyleneglycol) orderivatives thereof.

Specific naturally occurring polymers include lactose, amylose, dextran,glycogen or derivatives thereof.

“Derivatives” as used herein is intended to include reactivederivatives, for example thiol-selective reactive groups such asmaleimides and the like. The reactive group may be linked directly orthrough a linker segment to the polymer. It will be appreciated that theresidue of such a group will in some instances form part of the productas the linking group between the antibody fragment and the polymer.

The size of the polymer may be varied as desired, but will generally bein an average molecular weight range from 500 Da to 50000 Da, forexample from 5000 to 40000 Da such as from 20000 to 40000 Da. Thepolymer size may in particular be selected on the basis of the intendeduse of the product for example ability to localize to certain tissuessuch as tumors or extend circulating half-life (for review see Chapman,2002, Advanced Drug Delivery Reviews, 54, 531-545). Thus, for example,where the product is intended to leave the circulation and penetratetissue, for example for use in the treatment of a tumour, it may beadvantageous to use a small molecular weight polymer, for example with amolecular weight of around 5000 Da. For applications where the productremains in the circulation, it may be advantageous to use a highermolecular weight polymer, for example having a molecular weight in therange from 20000 Da to 40000 Da.

Suitable polymers include a polyalkylene polymer, such as apoly(ethyleneglycol) or, especially, a methoxypoly(ethyleneglycol) or aderivative thereof, and especially with a molecular weight in the rangefrom about 15000 Da to about 40000 Da.

In one example antibodies for use in the present invention are attachedto poly(ethyleneglycol) (PEG) moieties. In one particular example theantibody is an antibody fragment and the PEG molecules may be attachedthrough any available amino acid side-chain or terminal amino acidfunctional group located in the antibody fragment, for example any freeamino, imino, thiol, hydroxyl or carboxyl group. Such amino acids mayoccur naturally in the antibody fragment or may be engineered into thefragment using recombinant DNA methods (see for example U.S. Pat. No.5,219,996; U.S. Pat. No. 5,667,425; WO98/25971, WO2008/038024). In oneexample the antibody molecule of the present invention is a modified Fabfragment wherein the modification is the addition to the C-terminal endof its heavy chain one or more amino acids to allow the attachment of aneffector molecule. Suitably, the additional amino acids form a modifiedhinge region containing one or more cysteine residues to which theeffector molecule may be attached. Multiple sites can be used to attachtwo or more PEG molecules.

Suitably PEG molecules are covalently linked through a thiol group of atleast one cysteine residue located in the antibody fragment. Eachpolymer molecule attached to the modified antibody fragment may becovalently linked to the sulphur atom of a cysteine residue located inthe fragment. The covalent linkage will generally be a disulphide bondor, in particular, a sulphur-carbon bond. Where a thiol group is used asthe point of attachment appropriately activated effector molecules, forexample thiol selective derivatives such as maleimides and cysteinederivatives may be used. An activated polymer may be used as thestarting material in the preparation of polymer-modified antibodyfragments as described above. The activated polymer may be any polymercontaining a thiol reactive group such as an α-halocarboxylic acid orester, e.g. iodoacetamide, an imide, e.g. maleimide, a vinyl sulphone ora disulphide. Such starting materials may be obtained commercially (forexample from Nektar, formerly Shearwater Polymers Inc., Huntsville,Ala., USA) or may be prepared from commercially available startingmaterials using conventional chemical procedures. Particular PEGmolecules include 20K methoxy-PEG-amine (obtainable from Nektar,formerly Shearwater; Rapp Polymere; and SunBio) and M-PEG-SPA(obtainable from Nektar, formerly Shearwater).

In one embodiment, the antibody is a modified Fab fragment or diFabwhich is PEGylated, i.e. has PEG (poly(ethyleneglycol)) covalentlyattached thereto, e.g. according to the method disclosed in EP 0948544or EP1090037 [see also “Poly(ethyleneglycol) Chemistry, Biotechnical andBiomedical Applications”, 1992, J. Milton Harris (ed), Plenum Press, NewYork, “Poly(ethyleneglycol) Chemistry and Biological Applications”,1997, J. Milton Harris and S. Zalipsky (eds), American Chemical Society,Washington, D.C. and “Bioconjugation Protein Coupling Techniques for theBiomedical Sciences”, 1998, M. Aslam and A. Dent, Grove Publishers, NewYork; Chapman, A. 2002, Advanced Drug Delivery Reviews 2002,54:531-545]. In one example PEG is attached to a cysteine in the hingeregion. In one example, a PEG modified Fab fragment has a maleimidegroup covalently linked to a single thiol group in a modified hingeregion. A lysine residue may be covalently linked to the maleimide groupand to each of the amine groups on the lysine residue may be attached amethoxypoly(ethyleneglycol) polymer having a molecular weight ofapproximately 20,000 Da. The total molecular weight of the PEG attachedto the Fab fragment may therefore be approximately 40,000 Da.

Particular PEG molecules include 2-[3-(N-maleimido)propionamido]ethylamide of N,N′-bis(methoxypoly(ethylene glycol) MW 20,000) modifiedlysine, also known as PEG2MAL40K (obtainable from Nektar, formerlyShearwater).

Alternative sources of PEG linkers include NOF who supply GL2-400MA2(wherein m in the structure below is 5) and GL2-400MA (where m is 2) andn is approximately 450:

That is to say each PEG is about 20,000 Da.

Further alternative PEG effector molecules of the following type:

are available from Dr Reddy, NOF and Jenkem.

In one embodiment there is provided an antibody which is PEGylated (forexample with a PEG described herein), attached through a cysteine aminoacid residue at or about amino acid 226 in the chain, for example aminoacid 226 of the heavy chain (by sequential numbering).

The present invention also provides an isolated DNA sequence encodingthe heavy and/or light chain(s) of an antibody molecule of the presentinvention. Suitably, the DNA sequence encodes the heavy or the lightchain of an antibody molecule of the present invention. The DNA sequenceof the present invention may comprise synthetic DNA, for instanceproduced by chemical processing, cDNA, genomic DNA or any combinationthereof. DNA sequences which encode an antibody molecule of the presentinvention can be obtained by methods well known to those skilled in theart. For example, DNA sequences coding for part or all of the antibodyheavy and light chains may be synthesised as desired from the determinedDNA sequences or on the basis of the corresponding amino acid sequences.

DNA coding for acceptor framework sequences is widely available to thoseskilled in the art and can be readily synthesised on the basis of theirknown amino acid sequences.

Standard techniques of molecular biology may be used to prepare DNAsequences coding for the antibody molecule of the present invention.Desired DNA sequences may be synthesised completely or in part usingoligonucleotide synthesis techniques. Site-directed mutagenesis andpolymerase chain reaction (PCR) techniques may be used as appropriate.

Examples of suitable DNA sequences are provided in FIGS. 2-12, inparticular SEQ ID NOs 11, 13, 15, 17, 19, 21, 23, 25, 27, 29, 31, 33,35, 37, 39, 41, 43, 45 and 47.

Other examples of suitable DNA sequences are provided in FIGS. 20, 22,24 and 26-38, in particular SEQ ID NO: 65, SEQ ID NO: 73, SEQ ID NO: 75,SEQ ID NO: 77, SEQ ID NO: 79, SEQ ID NO: 81 and SEQ ID NO: 83.

The present invention also relates to a cloning or expression vectorcomprising one or more DNA sequences of the present invention.Accordingly, provided is a cloning or expression vector comprising oneor more DNA sequences encoding an antibody of the present invention.Suitably, the cloning or expression vector comprises two DNA sequences,encoding the light chain and the heavy chain of the antibody molecule ofthe present invention, respectively and suitable signal sequences. Inone example the vector comprises an intergenic sequence between theheavy and the light chains (see WO03/048208).

General methods by which the vectors may be constructed, transfectionmethods and culture methods are well known to those skilled in the art.In this respect, reference is made to “Current Protocols in MolecularBiology”, 1999, F. M. Ausubel (ed), Wiley Interscience, New York and theManiatis Manual produced by Cold Spring Harbor Publishing.

Also provided is a host cell comprising one or more cloning orexpression vectors comprising one or more DNA sequences encoding anantibody of the present invention. Any suitable host cell/vector systemmay be used for expression of the DNA sequences encoding the antibodymolecule of the present invention. Bacterial, for example E. coli, andother microbial systems may be used or eukaryotic, for examplemammalian, host cell expression systems may also be used. Suitablemammalian host cells include CHO, myeloma or hybridoma cells.

The present invention also provides a process for the production of anantibody molecule according to the present invention comprisingculturing a host cell containing a vector of the present invention underconditions suitable for leading to expression of protein from DNAencoding the antibody molecule of the present invention, and isolatingthe antibody molecule.

The antibody molecule may comprise only a heavy or light chainpolypeptide, in which case only a heavy chain or light chain polypeptidecoding sequence needs to be used to transfect the host cells. Forproduction of products comprising both heavy and light chains, the cellline may be transfected with two vectors, a first vector encoding alight chain polypeptide and a second vector encoding a heavy chainpolypeptide. Alternatively, a single vector may be used, the vectorincluding sequences encoding light chain and heavy chain polypeptides.

The antibodies and fragments according to the present disclosure areexpressed at good levels from host cells. Thus the properties of theantibodies and/or fragments are optimised and conducive to commercialprocessing.

As the antibodies of the present invention are useful in the treatmentand/or prophylaxis of a pathological condition, the present inventionalso provides a pharmaceutical or diagnostic composition comprising anantibody molecule of the present invention in combination with one ormore of a pharmaceutically acceptable excipient, diluent or carrier.Accordingly, provided is the use of an antibody of the invention for themanufacture of a medicament. The composition will usually be supplied aspart of a sterile, pharmaceutical composition that will normally includea pharmaceutically acceptable carrier. A pharmaceutical composition ofthe present invention may additionally comprise apharmaceutically-acceptable adjuvant.

The present invention also provides a process for preparation of apharmaceutical or diagnostic composition comprising adding and mixingthe antibody molecule of the present invention together with one or moreof a pharmaceutically acceptable excipient, diluent or carrier.

The antibody molecule may be the sole active ingredient in thepharmaceutical or diagnostic composition or may be accompanied by otheractive ingredients including other antibody ingredients, for exampleanti-TNF, anti-IL-1β, anti-T cell, anti-IFNγ or anti-LPS antibodies, ornon-antibody ingredients such as xanthines.

In a further embodiment the antibody, fragment or composition accordingto the disclosure is employed in combination with a furtherpharmaceutically active agent, for example a corticosteroid (such asfluticasonoe propionate) and/or a beta-2-agonist (such as salbutamol,salmeterol or formoterol) or inhibitors of cell growth and proliferation(such as rapamycin, cyclophosphmide, methotrexate) or alternative a CD28and for CD40 inhibitor. In one embodiment the inhibitor is a smallmolecule. In another embodiment the inhibitor is an antibody specific tothe target.

The pharmaceutical compositions suitably comprise a therapeuticallyeffective amount of the antibody of the invention. The term“therapeutically effective amount” as used herein refers to an amount ofa therapeutic agent needed to treat, ameliorate or prevent a targeteddisease or condition, or to exhibit a detectable therapeutic orpreventative effect. For any antibody, the therapeutically effectiveamount can be estimated initially either in cell culture assays or inanimal models, usually in rodents, rabbits, dogs, pigs or primates. Theanimal model may also be used to determine the appropriate concentrationrange and route of administration. Such information can then be used todetermine useful doses and routes for administration in humans.

The precise therapeutically effective amount for a human subject willdepend upon the severity of the disease state, the general health of thesubject, the age, weight and gender of the subject, diet, time andfrequency of administration, drug combination(s), reaction sensitivitiesand tolerance/response to therapy. This amount can be determined byroutine experimentation and is within the judgment of the clinician.Generally, a therapeutically effective amount will be from 0.01 mg/kg to50 mg/kg, for example 0.1 mg/kg to 20 mg/kg. Pharmaceutical compositionsmay be conveniently presented in unit dose forms containing apredetermined amount of an active agent of the invention per dose.

Compositions may be administered individually to a patient or may beadministered in combination (e.g. simultaneously, sequentially orseparately) with other agents, drugs or hormones.

The dose at which the antibody molecule of the present invention isadministered depends on the nature of the condition to be treated, theextent of the inflammation present and on whether the antibody moleculeis being used prophylactically or to treat an existing condition.

The frequency of dose will depend on the half-life of the antibodymolecule and the duration of its effect. If the antibody molecule has ashort half-life (e.g. 2 to 10 hours) it may be necessary to give one ormore doses per day. Alternatively, if the antibody molecule has a longhalf life (e.g. 2 to 15 days) it may only be necessary to give a dosageonce per day, once per week or even once every 1 or 2 months.

The pharmaceutically acceptable carrier should not itself induce theproduction of antibodies harmful to the individual receiving thecomposition and should not be toxic. Suitable carriers may be large,slowly metabolised macromolecules such as proteins, polypeptides,liposomes, polysaccharides, polylactic acids, polyglycolic acids,polymeric amino acids, amino acid copolymers and inactive virusparticles.

Pharmaceutically acceptable salts can be used, for example mineral acidsalts, such as hydrochlorides, hydrobromides, phosphates and sulphates,or salts of organic acids, such as acetates, propionates, malonates andbenzoates.

Pharmaceutically acceptable carriers in therapeutic compositions mayadditionally contain liquids such as water, saline, glycerol andethanol. Additionally, auxiliary substances, such as wetting oremulsifying agents or pH buffering substances, may be present in suchcompositions. Such carriers enable the pharmaceutical compositions to beformulated as tablets, pills, dragees, capsules, liquids, gels, syrups,slurries and suspensions, for ingestion by the patient.

Suitable forms for administration include forms suitable for parenteraladministration, e.g. by injection or infusion, for example by bolusinjection or continuous infusion. Where the product is for injection orinfusion, it may take the form of a suspension, solution or emulsion inan oily or aqueous vehicle and it may contain formulatory agents, suchas suspending, preservative, stabilising and/or dispersing agents.Alternatively, the antibody molecule may be in dry form, forreconstitution before use with an appropriate sterile liquid.

Once formulated, the compositions of the invention can be administereddirectly to the subject. The subjects to be treated can be animals.However, in one or more embodiments the compositions are adapted foradministration to human subjects.

Suitably in formulations according to the present disclosure, the pH ofthe final formulation is not similar to the value of the isoelectricpoint of the antibody or fragment, for example if the pH of theformulation is 7 then a pI of from 8-9 or above may be appropriate.Whilst not wishing to be bound by theory it is thought that this mayultimately provide a final formulation with improved stability, forexample the antibody or fragment remains in solution.

In one embodiment the pharmaceutical formulation at a pH in the range of4.0 to 7.0 comprises: 1 to 200 mg/mL of an antibody according to thepresent disclosure, 1 to 100 mM of a buffer, 0.001 to 1% of asurfactant, a) 10 to 500 mM of a stabiliser, b) 10 to 500 mM of astabiliser and 5 to 500 mM of a tonicity agent, or c) 5 to 500 mM of atonicity agent.

For example the formulation at approximately pH6 may comprise 1 to 50mg/mL of antibody, 20 mM L-histadine HCl, 240 mM trehalose and 0.02%polysorbate 20. Alternatively a formulation at approximately pH 5.5 maycomprise 1 to 50 mg/mL of antibody, 20 mM citrate buffer, 240 mMsucrose, 20 mM arginine, and 0.02% polysorbate 20.

The pharmaceutical compositions of this invention may be administered byany number of routes including, but not limited to, oral, intravenous,intramuscular, intra-arterial, intramedullary, intrathecal,intraventricular, transdermal, transcutaneous (for example, seeWO98/20734), subcutaneous, intraperitoneal, intranasal, enteral,topical, sublingual, intravaginal or rectal routes. Hyposprays may alsobe used to administer the pharmaceutical compositions of the invention.Typically, the therapeutic compositions may be prepared as injectables,either as liquid solutions or suspensions. Solid forms suitable forsolution in, or suspension in, liquid vehicles prior to injection mayalso be prepared.

Direct delivery of the compositions will generally be accomplished byinjection, subcutaneously, intraperitoneally, intravenously orintramuscularly, or delivered to the interstitial space of a tissue. Thecompositions can also be administered into a lesion. Dosage treatmentmay be a single dose schedule or a multiple dose schedule.

It will be appreciated that the active ingredient in the compositionwill be an antibody molecule. As such, it will be susceptible todegradation in the gastrointestinal tract. Thus, if the composition isto be administered by a route using the gastrointestinal tract, thecomposition will need to contain agents which protect the antibody fromdegradation but which release the antibody once it has been absorbedfrom the gastrointestinal tract.

A thorough discussion of pharmaceutically acceptable carriers isavailable in Remington's Pharmaceutical Sciences (Mack PublishingCompany, N.J. 1991).

In one embodiment the formulation is provided as a formulation fortopical administrations including inhalation.

Suitable inhalable preparations include inhalable powders, meteringaerosols containing propellant gases or inhalable solutions free frompropellant gases. Inhalable powders according to the disclosurecontaining the active substance may consist solely of the abovementionedactive substances or of a mixture of the abovementioned activesubstances with physiologically acceptable excipient.

These inhalable powders may include monosaccharides (e.g. glucose orarabinose), disaccharides (e.g. lactose, saccharose, maltose), oligo-and polysaccharides (e.g. dextrans), polyalcohols (e.g. sorbitol,mannitol, xylitol), salts (e.g. sodium chloride, calcium carbonate) ormixtures of these with one another. Mono- or disaccharides are suitablyused, the use of lactose or glucose, particularly but not exclusively inthe form of their hydrates.

Particles for deposition in the lung require a particle size less than10 microns, such as 1-9 microns for example from 0.1 to 5 μm, inparticular from 1 to 5 μm. The particle size of the active ingredient(such as the antibody or fragment) is of primary importance.

The propellant gases which can be used to prepare the inhalable aerosolsare known in the art. Suitable propellant gases are selected from amonghydrocarbons such as n-propane, n-butane or isobutane andhalohydrocarbons such as chlorinated and/or fluorinated derivatives ofmethane, ethane, propane, butane, cyclopropane or cyclobutane. Theabovementioned propellant gases may be used on their own or in mixturesthereof.

Particularly suitable propellant gases are halogenated alkanederivatives selected from among TG 11, TG 12, TG 134a and TG227. Of theabovementioned halogenated hydrocarbons, TG134a(1,1,1,2-tetrafluoroethane) and TG227 (1,1,1,2,3,3,3-heptafluoropropane)and mixtures thereof are particularly suitable.

The propellant-gas-containing inhalable aerosols may also contain otheringredients such as cosolvents, stabilisers, surface-active agents(surfactants), antioxidants, lubricants and means for adjusting the pH.All these ingredients are known in the art.

The propellant-gas-containing inhalable aerosols according to theinvention may contain up to 5% by weight of active substance. Aerosolsaccording to the invention contain, for example, 0.002 to 5% by weight,0.01 to 3% by weight, 0.015 to 2% by weight, 0.1 to 2% by weight, 0.5 to2% by weight or 0.5 to 1% by weight of active ingredient.

Alternatively topical administrations to the lung may also be byadministration of a liquid solution or suspension formulation, forexample employing a device such as a nebulizer, for example, a nebulizerconnected to a compressor (e.g., the Pari LC-Jet Plus® nebulizerconnected to a Pari Master® compressor manufactured by Pari RespiratoryEquipment, Inc., Richmond, Va.).

The antibody of the invention can be delivered dispersed in a solvent,e.g., in the form of a solution or a suspension. It can be suspended inan appropriate physiological solution, e.g., saline or otherpharmacologically acceptable solvent or a buffered solution. Bufferedsolutions known in the art may contain 0.05 mg to 0.15 mg disodiumedetate, 8.0 mg to 9.0 mg NaCl, 0.15 mg to 0.25 mg polysorbate, 0.25 mgto 0.30 mg anhydrous citric acid, and 0.45 mg to 0.55 mg sodium citrateper 1 ml of water so as to achieve a pH of about 4.0 to 5.0. Asuspension can employ, for example, lyophilised antibody.

The therapeutic suspensions or solution formulations can also containone or more excipients. Excipients are well known in the art and includebuffers (e.g., citrate buffer, phosphate buffer, acetate buffer andbicarbonate buffer), amino acids, urea, alcohols, ascorbic acid,phospholipids, proteins (e.g., serum albumin), EDTA, sodium chloride,liposomes, mannitol, sorbitol, and glycerol. Solutions or suspensionscan be encapsulated in liposomes or biodegradable microspheres. Theformulation will generally be provided in a substantially sterile formemploying sterile manufacture processes.

This may include production and sterilization by filtration of thebuffered solvent/solution used for the formulation, aseptic suspensionof the antibody in the sterile buffered solvent solution, and dispensingof the formulation into sterile receptacles by methods familiar to thoseof ordinary skill in the art.

Nebulizable formulation according to the present disclosure may beprovided, for example, as single dose units (e.g., sealed plasticcontainers or vials) packed in foil envelopes. Each vial contains a unitdose in a volume, e.g., 2 mL, of solvent/solution buffer.

The antibodies disclosed herein may be suitable for delivery vianebulisation.

It is also envisaged that the antibody of the present invention may beadministered by use of gene therapy. In order to achieve this, DNAsequences encoding the heavy and light chains of the antibody moleculeunder the control of appropriate DNA components are introduced into apatient such that the antibody chains are expressed from the DNAsequences and assembled in situ.

The present invention also provides an antibody molecule (orcompositions comprising same) for use in the control of inflammatorydiseases, for example acute or chronic inflammatory disease. Suitably,the antibody molecule (or compositions comprising same) can be used toreduce the inflammatory process or to prevent the inflammatory process.In one embodiment there is provided an in vivo reduction of activated Tcells, in particular those involved in inappropriate inflammatory immuneresponses, for example recruited to the vicinity/location of such aresponse.

Reduction of activated T cells, as employed herein, may be a reduction,10, 20, 30, 40, 50, 60, 70, 80, 90 or more percent in comparison tobefore treatment or without treatment. Advantageously, treatment with anantibody, fragment or composition according to the present invention,may allow the reduction in the level of activated T cells, withoutreducing the patients general level of T cells (unactivated T cells).This may result in fewer side effects, and possibly prevent T celldepletion in the patient.

The present invention also provides the antibody molecule of the presentinvention for use in the treatment or prophylaxis of an immune disorder.The immune disorder, may, for example be selected from the groupconsisting of infections (viral, bacterial, fungal and parasitic),endotoxic shock associated with infection, arthritis, rheumatoidarthritis, asthma, COPD, pelvic inflammatory disease, Alzheimer'sDisease, inflammatory bowel disease, Crohn's disease, ulcerativecolitis, Peyronie's Disease, coeliac disease, gallbladder disease,Pilonidal disease, peritonitis, psoriasis, vasculitis, surgicaladhesions, stroke, Type I Diabetes, lyme disease, arthritis,meningoencephalitis, autoimmune uveitis, immune mediated inflammatorydisorders of the central and peripheral nervous system such as multiplesclerosis, lupus (such as systemic lupus erythematosus) andGuillain-Barr syndrome, Atopic dermatitis, autoimmune hepatitis,fibrosing alveolitis, Grave's disease, IgA nephropathy, idiopathicthrombocytopenic purpura, Meniere's disease, pemphigus, primary biliarycirrhosis, sarcoidosis, scleroderma, Wegener's granulomatosis, otherautoimmune disorders, pancreatitis, trauma (surgery), graft-versus-hostdisease, transplant rejection, heart disease including ischaemicdiseases such as myocardial infarction as well as atherosclerosis,intravascular coagulation, bone resorption, osteoporosis,osteoarthritis, periodontitis and hypochlorhydia, or infertility relatedto lack of fetal-maternal tolerance.

In one embodiment the antibody according to the invention is employed inthe treatment of allergy, COPD, autoimmune disease or rheumatoidarthritis.

The present invention also provides an antibody molecule according tothe present invention for use in the treatment or prophylaxis of pain,particularly pain associated with inflammation.

The present invention further provides the use of an antibody molecule,fragment or composition according to the present invention in themanufacture of a medicament for the treatment or prophylaxis of animmune disorder, in particular the immune disorder is rheumatoidarthritis, asthma or COPD.

The present invention further provides the use of an antibody molecule,fragment or composition according to the present invention in themanufacture of a medicament for the treatment or prophylaxis of one ormore medical indications described herein.

An antibody molecule, fragment or composition of the present inventionmay be utilised in any therapy where it is desired to increase theeffects of PD-1 in the human or animal body.

In one embodiment the antibody molecule of the present invention or acomposition comprising the same is used for the control of inflammatorydisease, e.g. as described herein.

The present invention also provides a method of treating human or animalsubjects suffering from or at risk of an immune disorder, the methodcomprising administering to the subject an effective amount of theantibody molecule of the present invention, or a composition comprisingthe same.

In one embodiment there is provided a process for purifying an antibody(in particular an antibody or fragment according to the invention)comprising the steps:

-   performing anion exchange chromatography in non-binding mode such    that the impurities are retained on the column and the antibody is    eluted.

Suitable ion exchange resins for use in the process include Q.FF resin(supplied by GE-Healthcare). The step may, for example be performed at apH about 8.

The process may further comprise an initial capture step employingcation exchange chromatography, performed for example at a pH of about 4to 5, such as 4.5. The cation exchange chromatography may, for exampleemploy a resin such as CaptoS resin or SP sepharose FF (supplied byGE-Healthcare). The antibody or fragment can then be eluted from theresin employing an ionic salt solution such as sodium chloride, forexample at a concentration of 200 mM.

Thus the chromatograph step or steps may include one or more washingsteps, as appropriate.

The purification process may also comprise one or more filtration steps,such as a dia filtration step.

Thus in one embodiment there is provided a purified anti-PD-1 antibodyor fragment, for example a humanised antibody or fragment, in particularan antibody or fragment according to the invention, in substantiallypurified from, in particular free or substantially free of endotoxinand/or host cell protein or DNA.

Purified form as used supra is intended to refer to at least 90% purity,such as 91, 92, 93, 94, 95, 96, 97, 98, 99% w/w or more pure.

Substantially free of endotoxin is generally intended to refer to anendotoxin content of 1 EU per mg antibody product or less such as 0.5 or0.1 EU per mg product.

Substantially free of host cell protein or DNA is generally intended torefer to host cell protein and/or DNA content 400 μg per mg of antibodyproduct or less such as 100 μg per mg or less, in particular 20 μg permg, as appropriate.

The antibody molecule of the present invention may also be used indiagnosis, for example in the in vivo diagnosis and imaging of diseasestates involving PD-1.

Comprising in the context of the present specification is intended tomeaning including.

Where technically appropriate embodiments of the invention may becombined.

Embodiments are described herein as comprising certainfeatures/elements. The disclosure also extends to separate embodimentsconsisting or consisting essentially of said features/elements.

The present invention is further described by way of illustration onlyin the following examples, which refer to the accompanying Figures, inwhich:

EXAMPLES

-   FIG. 1 in detail:-   a) Light chain V region of antibody 949 (SEQ ID NO:8)-   b) Heavy chain V region of antibody 949 (SEQ ID NO:9)-   c) CDRH1 (SEQ ID NO:1), CDRH2 (SEQ ID NO:2), CDRH3 (SEQ ID NO:3),    CDRL1 (SEQ ID NO:4), CDRL2 (SEQ ID NO:5), CDRL3 (SEQ ID NO:6) of    antibody 949)-   FIG. 2    -   a) Modified CDRL3 (deamidation site modified)    -   b) 949 VK1 gL1 V region (SEQ ID NO:10)    -   c) 949 VK1 gL1 V region DNA (SEQ ID NO:11)    -   d) 949 VK1 gL1 V region with signal sequence (SEQ ID NO:12)    -   e) 949 VK1 gL1 V region DNA with signal sequence (SEQ ID NO:13)    -   f) 949 VK1 gL1 light chain V+constant (SEQ ID NO:14)-   FIG. 3    -   a) 949 VK1 gL1 light chain V+constant DNA (SEQ ID NO:15)    -   b) 949 VK1 gL1 light chain V+constant with signal sequence (SEQ        ID NO:16)    -   c) 949 VK1 gL1 light chain V+constant DNA with signal sequence        (SEQ ID NO:17)    -   d) 949 VK1 gL9 V region (SEQ ID NO:18)-   FIG. 4    -   a) 949 VK1 gL9 V region DNA (SEQ ID NO:19)    -   b) 949 VK1 gL11 V region (SEQ ID NO:20)    -   c) 949 VK1 gL11 V region DNA (SEQ ID NO:21)    -   d) 949 VK1 gL12 V region (SEQ ID NO:22)    -   e) 949 VK1 gL12 V region DNA (SEQ ID NO:23)    -   f) 949 VK1 gL14 V region (SEQ ID NO:24)-   FIG. 5    -   a) 949 VK1 gL14 V region DNA (SEQ ID NO:25)    -   b) 949 VK3 gL1 V region (SEQ ID NO:26)    -   c) 949 VK3 gL1 V region DNA (SEQ ID NO:27)    -   d) 949 VK3 gL11 V region (SEQ ID NO:28)    -   e) 949 VK3 gL11 V region DNA (SEQ ID NO:29)    -   f) 949 gH1a V region (SEQ ID NO:30)-   FIG. 6    -   a) 949 gH1a V region DNA (SEQ ID NO:31)    -   b) 949 gH1a V region with signal sequence (SEQ ID NO:32)    -   c) 949 gH1a V region with signal sequence DNA (SEQ ID NO:33)    -   d) 949 gH1a V region and constant region (SEQ ID NO:34)-   FIG. 7    -   a) 949 gH1a V region and constant region DNA (SEQ ID NO:35)-   FIG. 8    -   a) 949 gH1a V region and constant region with signal sequence        (SEQ ID NO:36)-   FIG. 9    -   a) 949 gH1a V region and constant region with signal sequence        DNA (SEQ ID NO:37)-   FIG. 10    -   a) 949 gH8a V region (SEQ ID NO:38)    -   b) 949 gH8a V region DNA (SEQ ID NO:39)    -   c) 949 gH20a V region (SEQ ID NO:40)    -   d) 949 gH20a V region DNA (SEQ ID NO:41)    -   e) 949 gH1b V region (SEQ ID NO:42)    -   f) 949 gH1b V region (SEQ ID NO:43)-   FIG. 11    -   a) 949 gH8b V region (SEQ ID NO:44)    -   b) 949 gH8b V region DNA (SEQ ID NO:45)    -   c) 949 gH20b V region (SEQ ID NO:46)    -   d) 949 gH20b V region DNA (SEQ ID NO:47)    -   e) Human VK1 2-1-(1) L23 JK4 acceptor framework (SEQ ID NO:48)    -   f) Human VK1 2-1-(1) L23 JK4 acceptor framework DNA (SEQ ID        NO:49)-   FIG. 12    -   a) Human VK3 6-1-(1) A27 JK4 acceptor framework (SEQ ID NO:50)    -   b) Human VK3 6-141) A27 JK4 acceptor framework DNA (SEQ ID        NO:51)    -   c) Human VH1 1-3 1-46 JH4 acceptor framework (SEQ ID NO:52)    -   d) Human VH1 1-3 1-46 JH4 acceptor framework DNA (SEQ ID NO:53)    -   e) Human VH1 1-2 1-e JH4 acceptor framework (SEQ ID NO:54)    -   f) Human VH1 1-2 1-e JH4 acceptor framework DNA (SEQ ID NO:55)-   FIG. 13 shows Inhibition of human CD4⁺ T cell proliferation by    antibody 949. CD4⁺ T cells were purified from human PBMCs by    negative selection and cultured with Dynalbeads coated with anti-CD3    plus control (BSA) or anti-PD-1 antibodies/recombinant PD-L2.    Proliferation (y-axis) was measured by ³H-thymidine incorporation at    day 6. Bars represent the % of maximal response (anti-CD3/BSA) and    are the mean+/−S.E.M. of 4 different donor cultures.-   FIG. 14 Ligand blocking assay with antibody 949. PD-1 expressing    HEK293 cells were pre-incubated with purified chimeric 949 or    humanised 949, or isotype matched positive and negative controls,    followed by incubation with recombinant PD-L2. Blocking of PD-L2 to    PD-1 by antibody 949 was assessed by revealing PD-L2 binding with an    anti-mouse IgG H+L PE conjugated antibody. Figures in parentheses    denote calculated concentration in μg/mL of humanised 949 added    during the pre-incubation stage.-   FIG. 15 Stimulation of SEAP from the human PD-1/CD28/TCRζ SEAP    reporter cell line by antibody 949. Dilutions of antibody were    incubated with reporter cells and the released SEAP determined. Data    was plotted as fold induction (signal/background signal).-   FIG. 16 Cross-reactivity of 949 chimeric and humanised grafts with    PD-1 from Cynomolgus and Rhesus monkeys. Binding of 949 grafts to    HEK293 cells transfected with empty vector (d), or PD-1 from human    (a), cynomolgus (b) or rhesus (c) was measured by flow cytometry.    Data is presented as geomean of PD-1 antibody associated    fluorescence.-   FIG. 17 shows an alignment of the light chains for the murine,    acceptor frameworks and humanised light chains. CDRs are in bold and    underlined. Donor residues are in bold, italic and are highlighted.-   FIG. 18 shows an alignment of the heavy chains for the murine,    acceptor frameworks and humanised heavy chains. CDRs are in bold and    underlined. Donor residues are in bold, italic and are highlighted.-   FIG. 19 shows 949gH1a heavy chain (V+constant−hu IgG4P delta Lys)    (SEQ ID NO:58)-   FIG. 20 949gH1a heavy chain (V+constant−hu IgG4P delta Lys, exons    underlined) (SEQ ID NO:59)-   FIG. 21 949gH1a heavy chain (V+constant−hu IgG4P delta Lys) with    signal sequence underlined and italicised (SEQ ID NO: 60)-   FIG. 22 949gH1a heavy chain (V+constant−hu IgG4P delta Lys, exons    underlined) with signal sequence underlined and italicised (SEQ ID    NO: 61)-   FIG. 23 949gH1a heavy chain (V+constant−hu IgG1 delta Lys) (SEQ ID    NO: 62)-   FIG. 24 949gH1a heavy chain (V+constant−hu IgG1 delta Lys, exons    underlined) (SEQ ID NO: 63)-   FIG. 25 949gH1a heavy chain (V+constant−hu IgG1 delta Lys) with    signal sequence underlined and italicised (SEQ ID NO:64)-   FIG. 26 949gH1a heavy chain (V+constant−hu IgG1 delta Lys exons    underlined) with signal sequence underlined and italicised (SEQ ID    NO: 65)-   FIG. 27-   (a) 49 VK1 gL15 V-region amino acid and nucleic acid sequence and a    corresponding amino acid sequence where a signal sequence is    included. (SEQ ID NO: 66)-   (b) 949 VK1 gL15 V-region (SEQ ID NO: 67)-   (c) 949 VK1 gL15 V-region with signal sequence underlined and    italicised (SEQ ID NO: 68)-   FIG. 28-   (a) 949 VK1 gL15 V-region nucleic acid sequence including a signal    sequence. Also shown is an amino acid sequence of a light chain    variable region and constant region. (SEQ ID NO: 69)-   (b) 949 VK1 gL15 light chain (V+constant) (SEQ ID NO: 70)-   FIG. 29-   (a) 949VK1 gL15 light chain variable and constant region nucleic    acid sequence. Also shown is a light chain amino acid sequence    including a signal sequence. (SEQ ID NO: 71)-   (b) 949 VK1 gL15 light chain with signal sequence underlined and    italicised (SEQ ID NO: 72)-   FIG. 30-   (a) 949 VK1 gL15 light chain with signal sequence underlined and    italicised (SEQ ID NO:73)-   FIG. 31-   (a) 949gH20b V-region with signal sequence underlined and italicized    (SEQ ID NO:74)-   (b) 949gH20b V-region with signal sequence underlined and italicized    (SEQ ID NO: 75)-   (c) 949gH20b heavy chain (V+constant−hu IgG4P delta Lys) (SEQ ID    NO:76)-   FIG. 32-   (a) 949gH20b heavy chain (V+constant−hu IgG4P delta Lys) (SEQ ID    NO:77)-   FIG. 33-   (a) 949gH20b heavy chain (V+constant−hu IgG4P delta Lys) with signal    sequence underlined and italicized (SEQ ID NO: 78)-   FIG. 34-   (a) 949gH20b heavy chain (V+constant−hu IgG4P delta Lys, exons    underlined) with signal sequence underlined and italicised (SEQ ID    NO: 79)-   FIG. 35-   (a) 949gH20b heavy chain (V+constant−hu IgG1 delta Lys) (SEQ ID    NO:80)-   FIG. 36-   (a) 949gH20b heavy chain (V+constant−hu IgG1 delta Lys, exons    underlined) (SEQ ID NO:81)-   FIG. 37-   (a) 949gH20b heavy chain (V+constant−hu IgG1 delta Lys) with signal    sequence underlined and italicized (SEQ ID NO:82)-   FIG. 38-   (a) 949gH20b heavy chain (V+constant−hu IgG1 delta Lys, exons    underlined) with signal sequence underlined and italicised (SEQ ID    NO: 83)-   FIG. 39 Ligand blocking binding assay for 949 VK1 gL9 gH20b, 949 VK1    gL15 g8a, 949 VK1 gL15 g8b, 949 VK1 gL15 gH20a, VK1 gL15 gH20b.-   FIGS. 40 and 41 Activated T-cell binding assay with various    constructs-   FIGS. 42 a) and b)—The various antibody constructs cross react with    human and cyno PD-1-   FIG. 43 shows an alignment of the light chains for the murine,    acceptor frameworks and humanised light chains. CDRs are in bold and    underlined. Donor residues are in bold, italic and are highlighted.

Example 1 Methods for Generation of Anti-PD-1 Antibody Clone 19

The generation of antibody clone 19 has already been described ininternational application WO2010/029434.

1.1 Myeloma Cell Line

For fusion the myeloma cell line SP2/0-Ag14 from the German Collectionof Microorganisms and Cell Cultures (DSMZ GmbH, Braunschweig) was used.This cell line is a hybrid between BALB/c spleen cells and the myelomacell line P3x63Ag8. The cells have been described as not synthesizing orsecreting immunoglobulin chains, being resistant to 8-azaguanine at 20μg/ml, and not growing in HAT (Hypoxanthine, Aminopterin, Thymidine)medium. The SP2/0 cells are routinely maintained in tissue cultureflasks in standard growth medium (with 10% FCS). A new aliquot of frozenSP2/0 cells was used after a period of 2 weeks in order to avoid theimplementation of HGPRT-positive revertants. The myeloma cells wereshown to be negative in all mycoplasma tests.

1.2 Antigens for Immunization and Screening

The recombinant protein PD-1Fc was prepared using the methods describedfor the production of CD28Fc (Evans et al. Nat Immunol. 6, 271-9 (2005))and concentrated to 5.1 mg/ml in 0.01 M HEPES, 150 mM NaCl, pH 7.4.SDS-PAGE analysis of the antigen run under reducing and non-reducingconditions established the purity of the protein to be >95%.

1.3 Immunization

Five mice (about 8 weeks old) were immunized via the intraperitonealcavity using an immunization protocol over 60 days. For immunization analum precipitate of the immunogen was prepared. The alum precipitate wasfreshly prepared for each boost. The mice were immunized with 50 μgprotein and boosted with 25 μg protein. Three mice were used for fusion.

1.4 General Handling of Cells

Cells were handled under sterile conditions using a laminar air-flowsystem, sterile materials and sterile solutions. Cells were incubated at37° C. in a humid atmosphere containing 5% carbon dioxide. Forcultivation of the hybridoma cells a complete growth medium (CGM)containing DMEM with supplements 2-mercaptoethanol, L-Glutamine,GlutaMax, HT, non essential amino acids, sodium pyruvate,antibiotics/antimycotic solution (in concentrations recommended by thesupplier) and FCS at different concentrations (10%, 15% or 20%) wasused.

1.5 Preparation of Spleen Cells and Cell Fusions

After asphyxiation of the three immunized mice in CO₂ spleens wereaseptically removed. A single cell suspension of pooled spleens wasprepared. The spleen cells and the myeloma cells were washed severaltimes with DMEM and fused twice in the presence of 1 ml 50% (w/v) PEG3550 (ratio spleen cells to SP2/0 2.5:1 and 2.4:1). The hybridomasproduced were resuspended in CGM containing 20% FCS and aminopterin (HATmedium). The cell suspension (140 Cl/well) of each fusion was plated outinto eight 96-well tissue culture flat-bottom plates (Corning-Costar)containing 140 Cl/well peritoneal exudate cells as feeder cells in CGMwith 20% FCS. The plates were incubated for 10 days. During this periodcells were fed two times with HAT medium. An aliquot of the spleen cellpreparation (about 8×10⁶ spleen cells) was cultivated 10 days in a wellof a 24-well plate and the cell culture supernatant served as positivecontrol in ELISA.

1.6 Screening Assay

An ELISA was used for screening of IgG in cell culture supernatants. 96well flat-bottom polystyrene microtiter plates (Greiner, Cat. No 655061)were coated with 50 μl/well PD-1Fc antigen (5 μg/ml) in 0.5 Mcarbonate/bicarbonate buffer, pH 9.6. After incubation overnight in amoist chamber at 4° C. the plates were washed with tris-buffered saline(TBS, 50 mM Tris, pH 7.8, 500 mM sodium chloride) containing 0.01%Triton X-100 (washing buffer) and blocked with 200 μl/well 2% FCS in TBS(blocking buffer) for 1 hour at room temperature (RT) on a shaker. Thewells were washed with washing buffer and 100 μl cell culturesupernatant was added in the appropriate well. Cell culture supernatantfrom SP 2/0 myeloma cells was used as a negative control. As positivecontrol cell culture supernatant from spleen cell culture was used. Theplates were incubated on a shaker for 1 h at RT, followed by severalwashes. For detection of bound antibodies plates were incubated with 50μl/well goat anti-mouse IgG (Fab specific) conjugated to alkalinephosphatase (1:5000) in blocking buffer for 1 h at RT on a shaker,followed by several washes and addition of 150 μl/well substrate buffer(2 mM 4-nitrophenyl phosphate in 5% diethanolamine+0.5 mM MgCl₂, pH9.8). The optical density (OD) was estimated in a 12-channel Dynex OpsysMR microplate reader at 405 nm. Wells with OD405 nm 2-fold higher thanthe OD405 nm of the average plate value were selected as positive.

1.7 Selection of Stable Antibody Producers

Cells from positive IgG producing cultures were transferred into wellsof a 48-well plate and cultivated for several days (depending on thegrowth characteristics of the cells). An ELISA on PD-1Fc and withoutprecoated antigen in order to select the specific binders was carriedout. The cells from ELISA-positive wells were frozen in freezing medium(90% FCS, 10% DMSO). An aliquot of the cells was further cultivated forproduction of cell culture supernatants for further characterization.

1.8 Limiting Dilution Cloning

As soon as positive wells were identified, hybridoma cells were clonedto reduce the risk of overgrowth by non-producing cells (first cloning).To ensure that the antibodies are truly monoclonal the hybridomas werecloned again (second cloning). The method of limiting dilution was usedfor both cloning procedures. IgG producing cells were distributed intoone 96 well plate containing feeder cells at a density of 1-3 cells perwell. After 8-10 days (depending on growth characteristics) all plateswere visually inspected under the microscope for detection of monoclonalgrowth. Culture supernatants from such wells were screened for specificimmunoglobulin content using the above-described screening assay. Theappropriate clones concerning growth characteristic and ELISA signalwere selected, transferred into wells of a 24-well plate and cultivatedfor some days. A screening assay was performed. This procedure wasrepeated two to three times. The appropriate subclone was selectedrespectively for the second cloning procedure or cultivation forcryopreservation. This procedure resulted in the production of ananti-PD-1 antibody known as Clone 19.

1.9 Preparation and Isotyping of Antibodies

Hybridoma supernatant was prepared and diluted into sterile, azide-freePBS. Purified stocks of monoclonal antibodies were isotyped at 1 μg/mlin PBS using the IsoStrip Mouse Monoclonal Antibody Isotyping Kit (SantaCruz; sc-24958). Clone 19 was found to be isotype IgG_(1K).

1.10 Sequencing of Clone 19

The genes encoding clone 19 were cloned and sequenced and are providedin FIG. 1. This antibody was named antibody CA051_(—)00949 (oftenabbreviated to 949).

Example 2 Characterisation and Selection of Antibody 949

2.1 Rationale for Antibody Selection

In order to generate a therapeutic reagent which is able to transduce aninhibitory signal to T cells through PD-1, an agonistic anti-PD-1monoclonal antibody was selected. Targeting the membrane proximalepitope with this antibody will ensure that it does not block thebinding of the endogenous ligands for PD-1 (PD-L1 or PD-L2). Therefore,the agonistic antibody will act in addition to, and may potentiate, anynatural inhibitory signals from the ligands being transduced throughPD-1. Humanised versions of this antibody will have potentialtherapeutic utility in a wide range of human diseases which involveinappropriate levels of T or B lymphocyte activation.

2.2 Analysis of PD-1 Agonism Induced by Antibody 949 on Human CD4⁺ TCells

To demonstrate that antibody 949 (parental variable regions, murineIgG1) can induce signaling through PD-1, it was tested for its abilityto inhibit T cell receptor (TCR)-derived activating signals. This wasachieved by covalently coupling 949, along with a TCR-activatinganti-CD3 antibody, to Dynalbeads. The beads were then added to culturesof primary human CD4⁺ T cells and the resultant proliferation measuredby ³H-thymidine incorporation after 6 days.

Tosyl-activated 4.5 μm Dynalbeads (M450; Invitrogen) were washed in 0.1Msterile phosphate buffer (pH 7.5) and loaded with 2 μg of anti-human CD3(clone OKT3) per 1×10⁷ beads at 37° C. for 8 h with continuous inversionmixing. The beads were then washed to remove unconjugated anti-CD3 andaliquots were secondarily coated with 3 μg of BSA, a non-agonisticcontrol anti-PD-1 antibody, 949 or recombinant human PD-L2.mFc per 1×10⁷beads at 37° C. for 19 h with continuous inversion mixing. Beads weresubsequently washed and incubated in 0.2M Tris/0.1% BSA (pH 8.5) for 3hours to inactivate free tosyl groups, followed by washing andre-suspension of beads in PBS/0.1% BSA/2 mM EDTA (pH 7.4). Equalanti-CD3 and antibody/ligand coating of the bead sets was confirmed bystaining the beads with fluorochrome-labelled isotype-specificantibodies and analysing by flow cytometry.

For human T cell proliferation studies, fresh heparinised blood wasdiluted 1:1 with RPMI and the lymphocytes isolated by density gradientseparation (Ficoll Hypaque). CD4⁺ T cells were purified from the wholePBMCs by negative selection using MACS (CD4⁺ T cell isolation Kit II;Miltenyi Biotec). 1×10⁵ human CD4⁺ T cells/well were cultured at a 1:1ratio with the coated beads in 96-well round-bottomed plates andincubated at 37° C./5% CO₂/100% humidity for 6 days. Proliferation wasmeasured after 6 days by addition of 0.5 μCi/well ³H-thymidine for thelast 6 hours of culture. Cells were harvested onto glass-fibre filtersand incorporated ³H-thymidine was measured by β-scintillation counting.

2.3 Results

The results in FIG. 13 show the day 6 proliferative response by humanCD4⁺ T cells measured in the presence of anti-CD3 plus anti-PD-1antibody or BSA control coated beads. The data are expressed aspercentage of the maximal response (anti-CD3 plus BSA control) and arethe mean of 4 different donor responses. CD4⁺ T cell proliferation wasinhibited by antibody 949, so that the average proliferation observedwas only 51.6% of the maximum. Similar inhibition of CD4⁺ T cellproliferation was seen with recombinant human PD-L2, utilised as apositive control for PD-1 signaling. In comparison, a non-agonisticanti-PD-1 mAb was used, which showed no effect on CD4⁺ T cellproliferation in this assay as expected. This demonstrates that antibody949 is capable of inducing agonistic signaling through PD-1, which leadsto inhibition of human CD4⁺ T cell responses.

Example 3 Humanisation of Antibody CA051_(—)00949

Antibody CA051_(—)00949 was humanised by grafting the complementaritydetermining regions (CDRs, FIG. 1 c) from the mouse antibody V-regionsonto human germline antibody V-region frameworks. In order to recoverthe activity of the antibody, a number of framework residues from themouse V-regions were also retained in the humanised sequence. Theseresidues were selected using the protocol outlined by Adair et al.(1991) (Humanised antibodies. WO91/09967). Alignments of the mouseantibody (donor) V-region sequences with the human germline antibody(acceptor) V-region sequences are shown in FIGS. 17 and 18 together withthe designed humanised sequences.

The CDRs grafted from the donor to the acceptor sequence are as definedby Kabat (Kabat et al. Sequence of proteins of immunological interest(1987). Bethesda, Md., National Institutes of Health, US), with theexception of CDR-H1 where the combined Chothia/Kabat definition is used(see Adair et al. (1991) Humanised antibodies. WO91/09967).

The heavy chain CDRs of antibody 949 were grafted onto the humanV-region VH1 1-3 1-46 plus JH4 J-region (V BASE,http://vbase.mrc-cpe.cam.ac.uk/). The heavy chain framework residues areall from the human germline gene, with the exception of residues 25, 37,41, 48, 71, 73 and 76 (Kabat numbering), where the donor residuesPhenylalanine (F25), Methionine (M37), Histidine (H41), Isoleucine(148), Valine (V71), Lysine (K73) and Threonine (T76) were retained,respectively. The Glutamine residue at position 1 of the human frameworkwas replaced with Glutamic acid (E1) to afford the expression andpurification of a homogeneous product: the conversion of Glutamine topyroGlutamate at the N-terminus of antibodies and antibody fragments iswidely reported. The resulting humanised sequence was named 949 gH1a. Analternative humanised heavy chain sequence, 949 gH1b, was created bygrafting the CDRs onto human V-region VH1 1-2 1-e plus JH4 J-region (VBASE, http://vbase.mrc-cpe.cam.ac.uk/). The heavy chain frameworkresidues are all from the human germline gene, with the exception ofresidues 25, 37, 41, 48, 71, 76 and 78 (Kabat numbering), where thedonor residues Phenylalanine (F25), Methionine (M37), Histidine (H41),Isoleucine (148), Valine (V71), Threonine (T76) and Valine (V78) wereretained, respectively. The Glutamine residue at position 1 of the humanframework was replaced with Glutamic acid (E1) to afford the expressionand purification of a homogeneous product.

Human V-region VK1 2-1-(1) L23 plus JK4 J-region (V BASE,http://vbase.mrc-cpe.cam.ac.uk/) was chosen as the acceptor for thelight chain CDRs. The light chain framework residues are all from thehuman germline gene, with the exception of residues 1, 2, 3, 4, 47, 60and 70 (Kabat numbering), where the donor residues Glutamaic acid (E1),Asparagine (N2), Valine (V3), Leucine (L4), Tryptophan (W47), Asparticacid (D60) and Serine (S70) were retained, respectively. The resultinghumanised sequence was named 949 VK1 gL1. An alternative humanised lightchain sequence, 949 VK3 gL1, was created by grafting the CDRs onto humanV-region VK3 6-1-(1) A27 plus JK4 J-region (V BASE,http://vbase.mrc-cpe.cam.ac.uk/). The light chain framework residues areall from the human germline gene, with the exception of residues 2, 47,58, 70, 71 and 85 (Kabat numbering), where the donor residues Asparagine(N2), Tryptophan (W47), Valine (V58), Serine (S70), Tyrosine (Y71) andThreonine (T85) were retained, respectively.

Genes encoding the humanised 949 VK1 gL1, 949 VK3 gL1, 949 gH1a and 949gH1b light and heavy chain V-region sequences were designed andconstructed by an automated synthesis approach by Entelechon GmbH.Oligonucleotide-directed mutagenesis was used to modify the genes tocreate variants of the humanized heavy chains (gH2a through to gH20a,and gH2b through to gH20b) and light chains (VK1 gL2 through to gL17,and VK3 gL2 through to gL17), and in some cases a deamidation site inCDRL3 was modified (FIG. 2 a). FIG. 27 a shows a light chain gL15comprising a modified CDRL3. The humanised 949 light chain V-region genesequences were cloned into the UCB-Celltech human light chain expressionvector pKH10.1, which contains DNA encoding the human Kappa chainconstant region (Km3 allotype). The humanised 949 heavy chain V-regiongene sequences were cloned into the UCB-Celltech human gamma-4 heavychain expression vector pVhγ4P FL, which contains DNA encoding the humangamma-4 heavy chain constant region with the hinge stabilising mutationS241P (Angal et al., Mol Immunol. 1993, 30(1):105-8), and also into aversion of the human gamma-4P heavy chain vector in which the codon forthe C-terminal Lysine residue has been removed, pVhγ4P delta Lys. Thehumanised 949 heavy chain V-region gene sequences were also cloned intothe UCB-Celltech human gamma-1 heavy chain expression vector pVhγ1 deltaLys, which contains DNA encoding the human gamma-1 heavy chain constantregion with the C-terminal Lysine residue removed. Transientco-transfection of light and heavy chain vectors into HEK293 suspensioncells was achieved using 293 Fectin (12347-019 Invitrogen), and gaveexpression of the humanised, recombinant 949 antibodies.

A number of different variants of the humanised heavy and light chainswere generated by including the CDRs in FIG. 1( c) derived from antibody949 and 2(a) CDRL3 from clone 19 with a modified deamidation site, andone or more of the donor residues listed below, depending on theframework used. The sequences are provided in FIGS. 2-11 and FIGS. 17 to38.

3.1 Ab949 residues for humanization VK1 Light chain 2-1-(1) L23 Kabatposition Human acceptor residue 1 Alanine 2 Isoleucine 3 Arginine 4Methionine 47 Phenylalanine 60 Serine 70 Aspartic acid

VK3 Light chain 6-1-(1) A27 Kabat position Human acceptor residue 2Isoleucine 47 Leucine 58 Isoleucine 70 Aspartic acid 71 Phenylalanine 85Valine

VH Heavy chain 1-3 1-46 Kabat position Human acceptor residue 25 Serine37 Valine 41 Proline 48 Methionine 71 Arginine 73 Threonine 76 Serine

VH Heavy chain 1-2 1-e Kabat position Human acceptor residue 25 Serine37 Valine 41 Proline 48 Methionine 71 Alanine 76 Serine 78 Alanine

Example 4 Characterisation of the Humanised Antibodies Generated inExample 3

4.1 Affinity

Binding Affinity Measurements

The assay format involved capture of 949 or humanised version thereof byimmobilised anti-human Fc and subsequent titration of the human PD-1over the captured surface.

BIA (Biamolecular Interaction Analysis) was performed using a BIAcore3000 (BIAcore AB). Affinipure F(ab′)₂ Fragment, goat anti-human IgG, Fcfragment specific (Jackson ImmunoResearch) was immobilised on a CM5Sensor Chip via amine coupling chemistry to a capture level of ≈6000response units (RUs). A blank surface was prepared in a similar way,omitting the Fc fragment from the procedure. HBS-EP buffer (10 mM HEPESpH 7.4, 0.15 M NaCl, 3 mM EDTA, 0.005% Surfactant P20, BIAcore AB) wasused as the running buffer with a flow rate of 10 μl/min. A 10 μlinjection of 949 IgG at ˜1 μg/mL was used to give ˜200RU capture by theimmobilised anti-human IgG-Fc. Human PD-1 was titrated over the captured949 or humanised variants at various concentrations (50 nM or below) ata flow rate of 30 μL/min. The surface was regenerated by a 10 μLinjection of 40 mM HCl, followed by a 5 μL injection of 5 mM NaOH at aflowrate of 10 μL/min.

Background subtraction binding curves were analysed using theBIAevaluation software (version 3.2) following standard procedures.Kinetic parameters were determined from the fitting algorithm.

Data for 949 and the various humanised versions are shown in Table 1.For all grafts tested except for 1, (VK1 gL11gH1a) affinity for PD-1 wasimproved compared to the 949 parental antibody. The chimeric containedthe 949 variable regions with human IgG4 constant domains.

TABLE 1 4.2 Analysis of ligand blocking activity of antibody 949 andhumanised versions of 949 Antibody ka (1/Ms) kd (1/s) KD (nM) 949parental 2.66E+05 1.35E−03 5.07 949 chimeric 1.95E+05 1.17E−03 5.98 949VK1gL1 gH1a 2.11E+05 7.82E−04 3.71 949 VK1 gL1 gH1b 1.91E+05 5.56E−042.92 949 VK1 gL11 gH1a 2.07E+05 1.15E−03 5.54 949 VK1 gL9 gH8a 2.45E+055.74E−04 2.35 949 VK1 gL9 gH20a 2.30E+05 7.27E−04 3.17 949 VK1 gL9 gH8b2.27E+05 5.32E−04 2.34 949 VK1 gL9 gH20b 2.47E+05 6.58E−04 2.66 949 VK1gL12 gH8a 2.34E+05 5.74E−04 2.46 949 VK1 gL12 gH20a 2.26E+05 7.66E−043.38 949 VK1 gL12 gH8b 2.22E+05 6.14E−04 2.77 949 VK1 gL12 gH20b2.20E+05 8.35E−04 3.80 949 VK1 gL14 gH8a 2.09E+05 9.92E−04 4.75 949 VK1gL14 gH8b 2.03E+05 8.88E−04 4.38 949 VK3 gL1 gH1a 2.10E+05 8.44E−04 4.02949 VK3 gL1 gH1b 2.07E+05 6.50E−04 3.14 949 VK3 gL11 gH1a 2.23E+051.09E−03 4.89 949 VK1 gL15 Gh2 2.37E+05 8.56E−04 3.61

PD-1 ligand binding assays were performed to determine if antibody 949(chimeric human IgG4 (parental V region), and humanised transient clonesof 949) had the capacity to block ligand binding. In these assays PD-1expressing HEK cells were incubated with purified or transientlyexpressed antibody supernatants for 30 minutes, followed by incubationwith recombinant human PD-L2.mFc fusion protein. Binding of thePD-L2.mFc to cell expressed PD-1 was then revealed with a PE-conjugatedanti-mouse IgG H+L antibody.

Method

HEK293 cells were transiently transfected by culturing at 5×10⁶/wellwith 5 μg human PD-1 DNA and 293 fectin (Invitrogen) overnight in 6 wellplates. The following day PD-1 expressing HEK293 cells were added to 96well U-plate at 1×10⁵/well in 50 μL and pre-incubated for 30 mins on icewith 50 μL of either human IgG4 control (10 μg/mL), or purified chimeric949 (10, 3.3 or 1.1 μg/mL), or control anti-PD-1 antibody (10, 3.3 or1.1 μg/mL), or 150 μL neat humanised 949 transient supernatants.Recombinant human PD-L2.mFc fusion protein was added to the cells at 0.3μg/mL final concentration for a further 30 minutes on ice. HEK cellswere washed twice in FACS buffer. Phycoerythrin conjugated anti-mouseH+L IgG was diluted 1/200 and added to the cell pellets at 50 μL perwell. Cells were incubated on ice for 30 minutes. Cells were washedtwice in FACS buffer and immediately acquired on the flow cytometer.

Results

The data in FIG. 14 shows PD-L2.mFc binding to PD-1 transfected HEKcells when pre-blocked with either control IgG4 or anti-PD-1 antibodies.Control IgG4 did not inhibit binding of PD-L2 to the cells as indicatedby an increase in geometric mean fluorescent intensity. Purified,chimeric 949 antibody did not inhibit PD-L2 binding to PD-1 expressingcells at concentrations between 1 and 10 μg/mL. A control anti-PD-1antibody with known ligand blocking properties did block PD-L2 bindingto PD-1 expressing cells at the concentrations tested, confirming thatligand blocking could be detected in this assay format. All humanisedversions of antibody 949 also did not inhibit PD-L2 binding to PD-1expressed on cells.

4.3 Analysis of Functional Activity of Antibody 949 and HumanisedVersions thereof

A reporter gene assay was developed using a Jurkat cell line whichstably expresses a chimeric receptor comprising the extracellular ligandbinding and transmembrane domains of human PD-1 and human CD28 signalingand human TCRζ intracellular domains. These cells have a reporter geneunder the control of an NFκB-dependent promoter and the cells producesecreted alkaline phosphatase (SEAP) when stimulated with recombinanthuman PD-Ligand 1 or 2, demonstrating that this reporter assay iscapable of detecting PD-1 agonism. The assay was used to compare thefunctional agonistic activity of the parental murine antibody 949 with arange of humanised constructs.

The human PD-1/CD28/TCRζ chimera construct was generated according tothe methods described in International Application WO 2007/060406.Jurkat cells were stably transfected with the human PD-1/CD28/TCRζchimera in the SEAP reporter vector. Cells were prepared in bulk andstored in liquid nitrogen until used. Cells were thawed and dispensed in15 μL aliquots of medium containing 30,000 cells per 384 well. Theantibody/construct was prepared at 4× final concentration in NM6 medium,and a 5 μL volume added to duplicate wells. After 18 hours incubation, 4μL of supernatant was assayed for SEAP activity as described in the packleaflet (Clontech, Great Escape™ SEAP). Activity was calculated as foldinduction (signal divided by background signal).

The data in FIG. 15 shows antibody 949 stimulated release of SEAP fromthe Jurkat human PD-1/CD28/TCRζ SEAP reporter cell line. The controlhuman antibody, CAN-1, did not stimulate release of SEAP. The originalCA949 construct, cLcH, and the construct VK1 gL12 gH8b produced similartitrations in the assay. Table 2 indicates that all the humanisedconstructs tested generated a SEAP response in this assay, demonstratingthat they have maintained their agonistic function after humanisation.

TABLE 2 Comparison of humanised versions of 949 in the humanPD-1/CD28/TCRζ SEAP reporter assay. EC50 values were calculated as theconcentration of antibody required to generate 50% of the maximal signalgenerated by that antibody EC50 (ug/mL) VK1 gL9 gH8a 0.22 VK1 gL9 gH8b0.23 VK1 gL9 gH20a 0.25 VK1 gL9 gH20b 0.27 VK1 gL12 gH8a 0.29 VK1 gL12gH8b 0.20 VK1 gL12 gH20a 0.18 VK1 gL12 gH20b 0.18 VK1 gL14 gH8a 0.15 VK1gL14 gH8b 0.11 949 cLcH 0.084.4 Flow Cytometry Analysis of 949 Chimeric and 949 Humanised GraftsBinding to HEK293 Human, Cynomolgus and Rhesus PD-1

To confirm that the humanised grafts of antibody 949 maintainedcross-reactivity with non-human primate PD-1, flow cytometry assays werecarried out with HEK293 suspension cells which had been transientlytransfected with DNA encoding full length human, cynomolgus or rhesusPD-1. HEK293 cells were transiently transfected by culturing at5×10⁶/well with 5 μg DNA and 293 fectin (Invitrogen) overnight in 6 wellplates. The following day human, cynomolgus or rhesus PD-1 expressingHEK293 cells were resuspended in 0.2% BSA (w/v) PBS+0.09% sodium azideand incubated for 1 hr at 4° C. with stated concentrations of 949chimeric, 949 humanised grafts, 949 chimeric (purified) or controlantibodies. Cells were washed with PBS and incubated with secondaryantibody—1:1000 FITC (Fab)2 Goat anti Human Fc specific (109-006-098Jackson) for 1 hr at 4° C. Analyses were performed on a FACSCalibur(Becton Dickinson).

The results are shown in FIG. 16. They indicate that i) all the graftsbind specifically to PD-1 expressing cells (FIG. 16 a, d), ii) they allretain human PD-1 binding equivalent to the original sequence (FIG. 16a) and iii) they all cross-react with PD-1 from cynomolgus (FIG. 16 b)and rhesus (FIG. 16 c) monkeys.

4.5 Ligand Blocking Assay

PD-1 transfect HEK293 cells with test antibody for 30 minutes on ice.Then a control CAN1.Fc or PD-L2mFc were added at 0.3 μg/mL for a further30 minutes on ice after which cells were washed and the ligand bindingrevealed with anti mouse IgG H+L PE. The results are shown in FIG. 39.In summary the results show that the various 949 constructs do notprevent ligand binding.

4.6 Activated T-Cell Binding Assay

Human T cells isolated from whole blood via MACS (pan T cell kit) andactivated with PHA-L (1 μg/ml) & IL-2 (1 ng/ml) for 3 days

Cells washed in FACS buffer and added to a 96-well plate at ˜1×105cell/well

Cells were incubated with samples for ½ hour on ice, and then washedtwice in FACS buffer.

Antibody samples (in duplicate) diluted ⅓ from 10 μg/ml or neat (6-pointtitration curve)

Samples include Clone 19 hIgG4, CDP850 (hIgG4 control) and transientsamples:

-   -   Transient #1=949 VK1 gL9 gH 20b (10.3 μg/ml)    -   Transient #2=949 VK1 gL15 gH 8a (8.5 μg/ml)    -   Transient #3=949 VK1 gL15 gH 8b (8.4 μg/ml)    -   Transient #4=949 VK1 gL15 gH 20a (8.53 μg/ml)    -   Transient #5=949 VK1 gL15 gH 20b (6.8 μg/ml)    -   Transient #6=mock (tested neat)

Cells were then incubated with reveal antibody (anti-human IgG H+L, PEconjugated, diluted to 1/200 in FACS buffer) for ½ hour on ice.

Cells were washed twice in FACS buffer and read on FACSCalibur 2(acquired ˜10 000 lymphocytes per sample). The results are shown in FIG.40.

The EC50's were all between 1-6 μg/ml

EC50's (ng/ml):

Clone 19 hIgG4: −1197 (unconstrained curve) or 3611 (top part curveconstrained to ˜45 geo mean)

Transient #1: 1142

Transient #2: 3147

Transient #3: 6092

Transient #4: 2889

Transient #5: 4096

It will of course be understood that the present invention has beendescribed by way of example only, is in no way meant to be limiting, andthat modifications of detail can be made within the scope of the claimshereinafter. Preferred features of each embodiment of the invention areas for each of the other embodiments mutatis mutandis. All publications,including but not limited to patents and patent applications, cited inthis specification are herein incorporated by reference as if eachindividual publication were specifically and individually indicated tobe incorporated by reference herein as though fully set forth.

What is claimed is:
 1. A humanised agonistic antibody which binds humanPD-1 comprising a heavy chain and a light chain wherein the variabledomain of the heavy chain comprises the sequence given in SEQ ID NO:1for CDR-H1, the sequence given in SEQ ID NO:2 for CDR-H2 and thesequence given in SEQ ID NO:3 for CDR-H3 and the variable domain of thelight chain comprises the sequence given in SEQ ID NO:4 for CDR-L1, thesequence given in SEQ ID NO:5 for CDR-L2 and the sequence given in SEQID NO:7 for CDR-L3.
 2. A humanised agonistic antibody according to claim1, which binds human PD-1 comprising a heavy chain wherein the variabledomain of the heavy chain comprises the sequence given in SEQ ID NO:1for CDR-H1, the sequence given in SEQ ID NO:2 for CDR-H2 and thesequence given in SEQ ID NO:3 for CDR-H3 and the heavy chain frameworkregion is derived from human sub-group sequence VH 1-3 1-46+JH4 (SEQ IDNO: 52).
 3. A humanised antibody according to claim 2 wherein theresidue at at least one of positions 25, 37, 41, 48, 71, 73 and 76 ofthe variable domain of the heavy chain is a donor residue.
 4. Ahumanised antibody according to claim 3 having the heavy chain variabledomain sequence given in SEQ ID NO:30, SEQ ID NO:38 or SEQ ID NO:40. 5.A humanised agonistic antibody according to claim 1, which binds humanPD-1 comprising a heavy chain wherein the variable domain of the heavychain comprises the sequence given in SEQ ID NO:1 for CDR-H1, thesequence given in SEQ ID NO:2 for CDR-H2 and the sequence given in SEQID NO:3 for CDR-H3 and the heavy chain framework region is derived fromhuman sub-group sequence VH 1-2 1-e+JH4 (SEQ ID NO: 54).
 6. A humanisedantibody according to claim 5 having the heavy chain variable domainsequence given in SEQ ID NO:46.
 7. A humanised antibody according toclaim 5 wherein the residue at, at least one of, positions 25, 37, 41,48, 71, 76 and 78 of the variable domain of the heavy chain is a donorresidue.
 8. A humanised antibody according to claim 7 having the heavychain variable domain sequence given in SEQ ID NO:42 or SEQ ID NO:44. 9.A humanised agonistic antibody according to claim 1, which binds humanPD-1 comprising a light chain wherein the variable domain of the lightchain comprises the sequence given in SEQ ID NO:4 for CDR-L1, thesequence given in SEQ ID NO:5 for CDR-L2 and the sequence given in SEQID NO:7 for CDR-L3 and the light chain framework region is derived fromhuman sub-group sequence VK1 2-1(1) L23+JK4 (SEQ ID NO:48).
 10. Ahumanised antibody according to claim 9 wherein the residue at, at leastone of positions 1, 2, 3, 4, 47, 60 and 70 of the variable domain of thelight chain is a donor residue.
 11. A humanised antibody according toclaim 10 having the light chain variable domain sequence given in SEQ IDNO:20, SEQ ID NO:24 or SEQ ID NO:66.
 12. A humanised agonistic antibodyaccording to claim 1, which binds human PD-1 comprising a light chainwherein the variable domain of the light chain comprises the sequencegiven in SEQ ID NO:4 for CDR-L1, the sequence given in SEQ ID NO:5 forCDR-L2 and the sequence given in SEQ ID NO:7 for CDR-L3 and the lightchain framework region is derived from human sub-group sequence VK36-1-(1) A27+JK4 (SEQ ID NO:50).
 13. A humanised antibody according toclaim 12 wherein the residue at least one of positions 2, 47, 58, 70, 71and 85 of the variable domain of the light chain is a donor residue. 14.A humanised antibody according to claim 13 having the light chainvariable domain sequence given in SEQ ID NO:28.
 15. A humanisedagonistic antibody according to claim 1 having a heavy chain comprisinga sequence selected from the group consisting of: SEQ ID NO:30, SEQ IDNO:38, SEQ ID NO:40, SEQ ID NO:42, SEQ ID NO:44 and SEQ ID NO:46 and alight chain comprising a sequence selected from the group consisting ofSEQ ID NO:20, SEQ ID NO:24, SEQ ID NO:28 and SEQ ID NO:66.
 16. Ahumanised agonistic antibody according to claim 1 having a heavy chaincomprising a sequence selected from the group consisting of: SEQ IDNO:46, SEQ ID NO:58, SEQ ID NO:62, SEQ ID NO:76 and SEQ ID NO:80 and alight chain comprising a sequence selected from the group consisting ofSEQ ID NO:20, SEQ ID NO:24, SEQ ID NO:28, SEQ ID NO:66 and SEQ ID NO:70.17. An agonistic antibody molecule according to claim 1, wherein theantibody molecule is selected from the group consisting of: a completeantibody molecule having full length heavy and light chains or afragment thereof, such as a Fab, modified Fab′, Fab′, F(ab′)₂, Fv, VH,VL or scFv fragment.
 18. A humanised agonistic antibody according toclaim 1, wherein the variable domain of the light chain comprises asequence having at least 80% identity or similarity to the light chainvariable domain of a light chain comprising a sequence selected from thegroup consisting of SEQ ID NO:20, SEQ ID NO:24, SEQ ID NO:28 and SEQ IDNO:66; and wherein the variable domain of the heavy chain comprises asequence having at least 80% identity or similarity to the heavy chainvariable domain of a heavy chain comprising a sequence selected from thegroup consisting of: SEQ ID NO:30, SEQ ID NO:38, SEQ ID NO:40, SEQ IDNO:42, SEQ ID NO:44 and SEQ ID NO:46.
 19. A humanised agonistic antibodyaccording to claim 1, wherein the variable domain of the light chaincomprises a sequence having at least 80% identity or similarity to thelight chain variable domain of a light chain comprising a sequenceselected from the group consisting of SEQ ID NO: 20, SEQ ID NO:24, SEQID NO:28, SEQ ID NO:66 and SEQ ID NO:70; and wherein the variable domainof the heavy chain comprises a sequence having at least 80% identity orsimilarity to the heavy chain variable domain of a heavy chaincomprising a sequence selected from the group consisting of: SEQ IDNO:46, SEQ ID NO:58, SEQ ID NO:62, SEQ ID NO:76 and SEQ ID NO:80.
 20. Ahumanised agonistic antibody according to claim 1 having a bindingaffinity for isolated human PD-1 (for example human extracellulardomain) of less than 5 nM.
 21. A pharmaceutical composition comprisingan antibody according to claim 1, in combination with one or more of apharmaceutically acceptable excipient, diluent or carrier.
 22. Apharmaceutical composition according to claim 21, additionallycomprising other active ingredients.
 23. A humanised agonistic antibodyaccording to claim 1, wherein the heavy chain framework region isderived from human sub-group sequence VH 1-2 1-e+JH4 (SEQ ID NO: 54),and the residue at, at least one of, positions 25, 37, 41, 48, 71, 76and 78 of the variable domain of the heavy chain is a donor residue; orderived from human sub-group sequence VH 1-3 1-46+JH4 (SEQ ID NO: 52),wherein a residue at at least one of positions 25, 37, 41, 48, 71, 73and 76 of the variable domain of the heavy chain is a donor residue; andthe light chain framework region is derived from human sub-groupsequence VK1 2-1(1) L23+JK4 (SEQ ID NO:48), and the residue at, at leastone of, positions 2, 47, 58, 70, 71 and 85 of the variable domain of thelight chain is a donor residue; or derived from human sub-group sequenceVK1 2-1(1) L23+JK4 (SEQ ID NO: 50), and the residue at, at least one of,positions 2, 47, 58, 70, 71 and 85 of the variable domain of the lightchain is a donor residue.